Part I

Rigs, Tools, and Well Construction Equipment

Air Rotary Rigs	Auger-Core-Rotary Drill Rigs
Auger Drill Rigs	Auger Drill Tools
Augers, Hollow Stem	Bailers and Sand Pumps
Bit Dressers and Tools	Bit Grinders
Bits, Horizontal and Tools	Boring Machines
Cable Guards	Cable Tool Bits
Cable Tool Drilling Rigs	Cable Tool Friction Wheels
Cable Tool Hammers	Cable Tool Jars
Cable Tool Sockets	Cable Tool Stems
Casing, Fabricated Steel	Casing, Fiberglass
Casing, Plastic	Casing, PVC
Casing, Stainless Steel	Casing, Teflon
Casing Hammers, Drill Through	Casing Tools, Spiders, and Slips
Cat Heads	Combination (Cable-Rotary) Rigs
Compressor Filters	Compressors
Core Drilling Tools	Core Drill Rigs
Couplings, Compressor	Data Logging Equipment
Development Pumps	Directional Drills
Direct Push Tooling	Diverters
Down-the-Hole Drills	Down-the-Hole Hammer Bits
Down-the-Hole Hammer Tools	Down-the-Hole TV Equipment
Drilling Fluid Desanders, Desilters	Drilling Muds and Additives
Drill Pipe	Drill Pipe Holders
Drill Pipe Joint Compounds	Drill Pipe Joints
Drill Pipe Tools	Drive and Pulling Heads
Drive Bushings	Drive Caps
Drive Couplings	Drive Shoes
Elevators	Fishing Tools
Generators	Geophysical Equipment and Testing Services
Grouting/Cementing Equipment	Hoisting Plugs
Horizontal Drilling Rigs	Hose Clamps
Hydrofracture Equipment
Jetting Tools	Lubricants
Monitor Pipe	Mud Pumps
Overburden Drilling Rigs, Percussion	Packers
Perforators	Pipe Coatings
Portable Mud Pits	Pump Setting Rigs
Rig Support Trucks, Water Trucks	Rope, Safety
Rope, Wire	Rotary Bits, Cone and Drag
Rotary Drill Collars	Rotary Drilling Rigs
Rotary Drilling Rigs, Reverse Type	Rotary Hammer Bits
Rotary Hammers	Rotary Kellys
Rotary Subs	Rotary Tables
Rubber Hose Clamps and Fittings	Service and Repair Rigs
Solids Separation Equipment	Stabilizers
Swivels	Tool Wrenches and Tongs
Underreamers	Water Level Measuring Equipment
Well Gravels	Well Probes
Well Screens and Points, Metal	Well Screens and Points, Nonmetal
Well Screens, Fiberglass	Well Seal Vents
Winches, Hoists, and Cranes

Air Rotary Rigs

Ackerman International Corp.

Davey Drill Division of Davey Kent Inc.

Deeprock Mfg.

Foremost Industries Inc.

Foremost Mobile

GEFCO -- The George E. Failing Co.

Givens International Sales

Gus Pech Mfg. Co. Inc.

Mid America Drilling Equipment Inc.

Schramm Inc.

Sun Machinery Corp.

Venture Drilling Supply

Walker-Neer Corp.

Wellmaster Pipe & Supply Inc.

Auger-Core-Rotary Drill Rigs

Boart Longyear Co.

Buffalo Well Products

Central Mine Equipment Co.

Davey Drill Division of Davey Kent Inc.

Deeprock Mfg.

Diedrich Drill Inc.

Foremost Mobile

GEFCO -- The George E. Failing Co.

Gus Pech Mfg. Co. Inc.

Schramm Inc.

SIMCO Drilling Equipment Inc.

Sun Machinery Corp.

Wellmaster Pipe & Supply Inc.

Auger Drill Rigs

AMS Inc.

Boart Longyear Co.

Buffalo Well Products

Central Mine Equipment Co.

Davey Drill Division of Davey Kent Inc.

Deeprock Mfg.

Diedrich Drill Inc.

Foremost Mobile

GEFCO -- The George E. Failing Co.

Gus Pech Mfg. Co. Inc.

Mid America Drilling Equipment Inc.

SIMCO Drilling Equipment Inc.

Sun Machinery Corp.

Wellmaster Pipe & Supply Inc.

Auger Drill Tools

AMS Inc.

Boart Longyear Co.

Buffalo Well Products

Central Mine Equipment Co.

Diedrich Drill Inc.

Foremost Mobile

GEFCO -- The George E. Failing Co.

Givens International Sales

McLaughlin Manufacturing Co.

Mills Machine Co.

Scorpion

Star Iron Works Inc.

Wellmaster Pipe & Supply Inc.

Augers, Hollow Stem

AMS Inc.

Boart Longyear Co.

Buffalo Well Products

Central Mine Equipment Co.

Diedrich Drill Inc.

Foremost Mobile

GEFCO -- The George E. Failing Co.

Givens International Sales

Mills Machine Co.

Wellmaster Pipe & Supply Inc.

Bailers and Sand Pumps

AMS Inc.

Atlantic Screen and Mfg. Inc.

Buffalo Well Products

Campbell Manufacturing Inc.

Mills Machine Co.

Monflex, Div. of Campbell Mfg.

Parkersburg Tool Co.

QED Environmental Systems Inc.

Star Iron Works Inc.

Titan Industries Inc.

Trident Tool Inc.

Wellmaster Pipe & Supply Inc.

Bit Dressers and Tools

Drillers Supply Inc.

Parkersburg Tool Co.

Bit Grinders

Ackerman International Corp.

Drillers Supply Inc.

Givens International Sales

SECOROC USA

Star Iron Works Inc.

Trident Tool Inc.

Venture Drilling Supply

Bits, Horizontal and Tools

Ackerman International Corp.

Christensen Products

Diedrich Drill Inc.

Ditch Witch/The Charles Machine Works Inc.

McLaughlin Manufacturing Co.

Mills Machine Co.

Numa

Sun Machinery Corp.

USA Rock Bit Inc.

Boring Machines

Ditch Witch/The Charles Machine Works Inc.

Gus Pech Mfg. Co. Inc.

McLaughlin Mfanufacturing Co.

Venture Drilling Supply

Cable Guards

American Granby Inc.

APSCO Inc.

Boshart Industries Inc.

Campbell Manufacturing Inc.

Maass Midwest

Merrill

Paige Electric Co. L.P.

Simmons Manufacturing Co.

Wellmaster Pipe & Supply Inc.

Cable Tool Bits

Ackerman International Corp.

Givens International Sales

Parkersburg Tool Co.

Trident Tool Inc.

Wellmaster Pipe & Supply Inc.

Cable Tool Drilling Rigs

Ackerman International

Buckeye Drilling Co.

GEFCO -- The George E. Failing Co.

Trident Tool

Walker-Neer Corp.

Wellmaster Pipe & Supply Inc.

Cable Tool Friction Wheels

Buckeye Drill Co.

Paper Pulleys Inc.

Trident Tool Inc.

Wellmaster Pipe & Supply Inc.

Cable Tool Hammers

Aardvark Corp.

Ackerman International Corp.

Trident Tool Inc.

Wellmaster Pipe & Supply Inc.

Cable Tool Jars

Ackerman International Corp.

Givens International Sales

Parkersburg Tool Co.

Trident Tool Inc.

Wellmaster Pipe & Supply Inc.

Cable Tool Sockets

Parkersburg Tool Co.

Trident Tool Inc.

Wellmaster Pipe & Supply Inc.

Cable Tool Stems

Ackerman International Corp.

Parkersburg Tool Co.

Star Iron Works Inc.

Trident Tool Inc.

Wellmaster Pipe & Supply Inc.

Casing, Fabricated Steel

Aardvark Corp.

APSCO Inc.

Buckeye Drill Co.

Christensen Products

Diedrich Drill Inc.

Foremost Mobile

Morris Industries Inc.

Nagaoka USA

National Well Supplies Co. Inc.

Roscoe Moss Co.

Wellmaster Pipe & Supply Inc.

Wheatland Tube Co.

Casing, Fiberglass

Buffalo Well Products

Burgess Well Co. Inc.

ENCO. EMC

Givens International Sales

Casing, Plastic

Aardvark Corp.

Atlantic Screen & Mfg. Inc.

Bedrock Enterprises Inc.

Buffalo Well Products

Campbell Manufacturing Inc.

CertainTeed Corp., Pipe & Plastics Group

Jet Stream Plastic Pipe Co.

Kilman Electriloc Inc.

Monflex, Div. of Campbell Mfg.

National Well Supplies Co. Inc.

RST Instruments Ltd.

Titan Industries Inc.

Wellmaster Pipe & Supply Inc.

Casing, PVC

Aardvark Corp.

APSCO Inc.

Atlantic Screen & Mfg. Inc.

Bedrock Enterprises Inc.

Boart Longyear Co.

Buffalo Well Products

Campbell Manufacturing Inc.

CertainTeed Corp., Pipe & Plastics Group

Diedrich Drill Inc.

Enviro Products Inc.

Givens International Sales

Jet Stream Plastic Pipe Co.

Kilman Electriloc Inc.

Monoflex, Div. of Campbell Mfg.

National Well Supplies Co. Inc.

Roscoe Moss Co.

RST Instruments Ltd.

TIMCO Manufacturing Inc.

Titan Industries Inc.

U.S. Filter/Johnson Screens

Wellmaster Pipe & Supply Inc.

Casing, Stainless Steel

APSCO Inc.

Atlantic Screen & Mfg. Inc.

Boart Longyear Co.

Buckeye Drill Co.

Buffalo Well Products

Christensen Products

Cook Screen Technologies Inc.

Diedrich Drill Inc.

Enviro Products Inc.

Flatwater Fleet Inc.

Givens International Sales

Nagaoka USA

National Well Supplies Co. Inc.

Roscoe Moss Co.

Titan Industries Inc.

U.S. Filter/Johnson Screens

Western Well Screen Mfg., Div. MWM Indus.

Casing, Teflon

APSCO Inc.

Atlantic Screen & Mfg. Inc.

Buffalo Well Products

Campbell Manufacturing Inc.

National Well Supplies Co. Inc.

TIMCO Manufacturing Inc.

Titan Industries Inc.

Casing Hammers, Drill Through

Aardvark Corp.

Weldco-Beales Inc.

Wellmaster Pipe & Supply Inc.

Casing Tools, Spiders, and Slips

Ackerman International Corp.

Foremost Mobile

Mills Machine Co.

Parkersburg Tool Co.

Star Iron Works Inc

Trident Tool Inc.

Cat Heads

Ackerman International Corp.

AMS Inc.

Buckeye Drill Co.

Diedrich Drill Inc.

Foremost Mobile

Combination (Cable-Rotary) Rigs

Ackerman International Corp.

Gus Pech Mfg. Co. Inc.

Sun Machinery Corp.

Walker-Neer Corp.

Compressor Filters

Atlas Copco Compressors Inc.

Venture Drilling Supply

Compressors

Atlas Copco Compressors Inc.

Foremost Mobile

Givens International Sales

Mid America Drilling Equipment Inc.

QED Environmental Systems Inc.

Schramm Inc.

Venture Drilling Supply

Core Drilling Tools

Boart Longyear Co.

Central Mine Equipment Co.

Christensen Products

Diedrich Drill Inc.

Foremost Mobile

Mills Machine Co.

Scorpion

Star Iron Works Inc.

Wellmaster Pipe & Supply Inc.

Core Drill Rigs

AMS Inc.

Boart Longyear Co.

Central Mine Equipment Co.

Christensen Products

Davey Drill Division of Davey Kent Inc.

Diedrich Drill Inc.

Foremost Mobile

GEFCO -- The George E. Failing Co.

Givens International Sales

Gus Pech Mfg. Co. Inc.

SIMCO Drilling Equipment Inc.

Sun Machinery Corp.

Walker-Neer Corp.

Wellmaster Pipe & Supply Inc.

Couplings, Compressor

Givens International Sales

Wellmaster Pipe & Supply Inc.

Data Logging Equipment

Campbell Manufacturing Inc.

Geokon Inc.

In-Situ Inc.

Keck Instruments Inc.

Monoflex, Div. of Campbell Mfg.

QED Environmental Systems Inc.

Roctest Inc.

RST Instruments Ltd.

Solinst Canada Ltd.

Stevens Water Monitoring Systems

Development Pumps

APSCO Inc.

Buffalo Well Products

Foremost Mobile

QED Environmental Systems Inc.

TIMCO Manufacturing Inc.

Trident Tool Inc.

Directional Drills

Ackerman International Corp.

Christensen Products

Ditch Witch/The Charles Machine Works Inc.

Foremost Mobile

GEFCO -- The George E. Failing Co.

McLaughlin Manufacturing Co.

Direct Push Tooling

AMS Inc.

Buffalo Well Products

Campbell Manufacturing Inc.

Diedrich Drill Inc.

Foremost Mobile

Hacker Industries

McLaughlin Manufacturing Co.

QED Environmental Systems Inc.

SIMCO Drilling Equipment Inc.

Solinst Canada Ltd.

Diverters

Washington Rotating Control Heads

Down-the-Hole Drills

Ackerman International Corp.

Davey Drill Division of Davey Kent Inc.

Deeprock Mfg.

Drillers Supply Inc.

Foremost Mobile

Givens International Sales

Numa

SECOROC USA

Sun Machinery Corp.

Venture Drilling Supply

Wellmaster Pipe & Supply Inc.

Down-the-Hole Hammer Bits

Ackerman International Corp.

Drillers Supply Inc.

Drillmaster International

Foremost Mobile

Givens International Sales

John K. Olsen Co. Inc.

Numa

SECOROC USA

Sun Machinery Corp.

Venture Drilling Supply

Wellmaster Pipe & Supply Inc.

Down-the-Hole Hammer Tools

Ackerman International Corp.

Drillers Supply Inc.

Drillmaster International

Foremost Mobile

John K. Olsen Co. Inc.

Numa

Scorpion

SECOROC USA

Venture Drilling Supply

Wellmaster Pipe & Supply Inc.

Down-the-Hole TV Equipment

APSCO Inc.

Campbell Manufacturing Inc.

CCV Eng. &; Mfg. WellCam/Boretech

Colog Inc.

Laval Underground Surveys

Marks Products Inc.

Mount Sopris Instruments

Drilling Fluid Desanders, Desilters

Double Life Corp. (The)

Driller Supply Inc.

Drilling Muds and Additives

APSCO Inc.

Baroid Industrial Drilling Products

Black Hills Bentonite LLC

Buffalo Well Products

CETCO

Drillers Supply Inc.

Economy Mud Products Co.

Federal Summit Fluids

Givens International Sales

Polymer Drilling Systems

Roscoe Moss Co.

Toney Drilling Supplies Inc.

Venture Drilling Supply

Wyo-Ben Inc.

Drill Pipe

Ackerman International Corp.

Central Mine Equipment Co.

Christensen Products

Diedrich Drill Inc.

Ditch Witch/The Charles Machine Works Inc.

Drillers Supply Inc.

Foremost Mobile

GEFCO -- The George E. Failing Co.

Givens International Sales

Hacker Industries

LTA Corp.

Mid America Drilling Equipment Inc.

Mills Machine Co.

SECOROC USA

Star Iron Works Inc.

Sun Machinery Corp.

Venture Drilling Supply

Wellmaster Pipe & Supply Inc.

Wheatland Tube Co.

Drill Pipe Holders

Baker Mfg. Co./Monitor Division

Drillers Supply Inc.

Foremost Mobile

GEFCO -- The George E. Failing Co.

Givens International Sales

Mills Machine Co.

Star Iron Works Inc.

Wellmaster Pipe & Supply Inc.

Drill Pipe Joint Compounds

Ackerman International Corp.

APSCO Inc.

Drillers Supply Inc.

Givens International Sales

Jet-Lube Inc.

Mills Machine Co.

Venture Drilling Supply

Wellmaster Pipe & Supply Inc.

Drill Pipe Joints

Ackerman International Corp.

Drillers Supply Inc.

GEFCO -- The George E. Failing Co.

Givens International Sales

Hacker Industries

LTA Corp.

Mills Machine Co.

Star Iron Works Inc.

Wellmaster Pipe & Supply Inc.

Drill Pipe Tools

Ackerman International Corp.

Drillers Supply Inc.

Foremost Mobile

GEFCO -- The George E. Failing Co.

Givens International Sales

Mills Machine Co.

Scorpion

Star Iron Works Inc.

Wellmaster Pipe & Supply Inc.

Drive and Pulling Heads

Parkersburg Tool Co.

Star Iron Works Inc.

Trident Tool Inc.

Drive Bushings

American Granby Inc.

Boshart Industries Inc.

GEFCO -- The George E. Failing Co.

Hacker Industries

Star Iron Works Inc.

Drive Caps

American Granby Inc.

AMS Inc.

Boshart Industries Inc.

Campbell Manufacturing Inc.

Cook Screen Technologies Inc.

Foremost Mobile

GEFCO -- The George E. Failing Co.

Maass Midwest

Merrill

Simmons Manufacturing Co.

Star Iron Works Inc.

Trident Tool Inc.

Drive Couplings

American Granby Inc.

AMS Inc.

Boshart Industries Inc.

Campbell Manufacturing Inc.

Cook Screen Technologies Inc.

Custom Pipe & Coupling

Foremost Mobile

GEFCO -- The George E. Failing Co.

Maass Midwest

Merrill

Simmons Manufacturing Co.

Wellmaster Pipe & Supply Inc.

Drive Shoes

American Granby Inc.

AMS Inc.

Brookman Cast Industries Inc.

Buckeye Drill Co.

Campbell Manufacturing Inc.

Custom Pipe & Coupling

Foremost Mobile

GEFCO -- The George E. Failing Co.

Givens International Sales

Hacker Industries

Maass Midwest

Morris Industries Inc.

Parkersburg Tool Co.

Roscoe Moss Co.

Star Iron Works Inc.

Trident Tool Inc.

Wellmaster Pipe & Supply Inc.

Elevators

Ackerman International Corp.

APSCO Inc.

Baker Mfg. Co./Monitor Division

Buffalo Well Products

Drillers Supply Inc.

Foremost Mobile

Givens International Sales

Mill Machine Co.

Parkersburg Tool Co.

Trident Tool Inc.

Walker-Neer Corp.

Wellmaster Pipe & Supply Inc.

Fishing Tools

Ackerman International Corp.

AMS Inc.

Campbell Manufacturing Inc.

Diedrich Drill Inc.

Drillers Supply Inc.

Foremost Mobile

GEFCO -- The George E. Failing Co.

Givens International Sales

LTA Corp.

Maass Midwest

McLaughlin Manufacturing Co.

Mill Machine Co.

Parkersburg Tool Co.

Star Iron Works Inc.

Trident Tool Inc.

Wellmaster Pipe & Supply Inc.

Generators

Atlas Copco Compressors Inc.

Geophysical Equipment and Testing Services

AMS Inc.

Colog Inc.

Foremost Mobile

Geonics Ltd.

Groundflow Ltd.

Keck Instruments Inc.

Mills Machine Co.

Mount Sopris Instruments

SAGA Geophysics Inc.

Grouting/Cementing Equipment

Aardvark Corp.

AMS Inc.

Baski Inc.

Flatwater Fleet Inc.

Foremost Mobile

GEFCO -- The George E. Failing Co.

International Pump Technology Inc.

Kyle Equipment Co. Inc.

Solinst Canada Ltd.

Venture Drilling Supply

Wellmaster Pipe & Supply Inc.

Hoisting Plugs

APSCO Inc.

Atlantic Screen & Mfg. Inc.

Bedrock Enterprises Inc.

Buffalo Well Products

Campbell Manufacturing Inc.

Cook Screen Technologies Inc.

Diedrich Drill Inc.

Foremost Mobile

GEFCO -- The George E. Failing Co.

Givens International Sales

Hacker Industries

Mill Machine Co.

Monoflex, Div. of Campbell Mfg.

Parkersburg Tool Co.

Star Iron Works Inc.

TIMCO Manufacturing Inc.

Titan Industries Inc.

Horizontal Drilling Rigs

Aardvark International Corp.

Central Mine Equipment Co.

Christensen Products

Ditch Witch/The Charles Machine Works Inc.

Foremost Mobile

McLaughlin Manufacturing Co.

Mill Machine Co.

Hose Clamps

American Granby Inc.

APSCO Inc.

Baker Mfg. Co./Monitor Division

Boshart Industries Inc.

Campbell Manufacturing Inc.

Maass Midwest

Merrill

Wellmaster Pipe & Supply Inc.

Hydrofracture Equipment

Baski Inc.

Flatwater Fleet Inc.

Kyle Equipment Co. Inc.

RST Instruments Ltd.

Star Iron Works Inc.

TAM International Inc.

Jetting Tools

Buffalo Well Products

Campbell Manufacturing Inc.

Flatwater Fleet Inc.

Kyle Equipment Co. Inc.

Mill Machine Co.

Lubricants

APSCO Inc.

CETCO

Givens International Sales

Jet-Lube Inc.

National Well Supplies Co. Inc.

Monitor Pipe

Aardvark Corp.

Bedrock Enterprises Inc.

Campbell Manufacturing Inc.

Diedrich Drill Inc.

Environmental Manufacturing Inc.

Johnson Well Equipment Inc.

Monoflex, Div. of Campbell Mfg.

RST Instruments Ltd.

TIMCO Manufacturing Inc.

Titan Industries Inc.

Western Well Screen Mfg., Div. MWM Indus.

Mud Pumps

Christensen Products

Double Life Corp. (The)

Drillers Supply Inc.

Foremost Mobile

GEFCO -- The George E. Failing Co.

Givens International Sales

LTA Corp.

Mid America Drilling Equipment Inc.

Sun Machinery Corp.

Wellmaster Pipe & Supply Inc.

Overburden Drilling Rigs, Percussion

Foremost Mobile

GEFCO -- The George E. Failing Co.

Mid America Drilling Equipment Inc.

Sun Machinery Corp.

Venture Drilling Supply

Walker-Neer Corp.

Wellmaster Pipe & Supply Inc.

Packers

Aardvark Corp.

Baski Inc.

Cook Screen Technologies Inc.

Flatwater Fleet Inc.

Givens International Sales

Jayco Screen Inc.

Keck Instruments Inc.

Kyle Equipment Co. Inc.

QED Environmental Systems Inc.

Roctest Inc.

RST Instruments Ltd.

Solinst Canada Ltd.

Star Iron Works Inc.

TAM International Inc.

U.S. Filter/Johnson Screens

Wellmaster Pipe & Supply Inc.

Western Well Screen Mfg., Div. MWM Indus.

Perforators

Parkersburg Tool Co.

Trident Tool Inc.

Pipe Coatings

Wellmaster Pipe & Supply Inc.

Portable Mud Pits

Ackerman International Corp.

Foremost Mobile

GEFCO -- The George E. Failing Co.

Mill Machine Co.

Polymer Drilling Systems

Wellmaster Pipe & Supply Inc.

Pump Setting Rigs

Flatwater Fleet Inc.

Kyle Equipment Co. Inc.

Pul-A-Pump Corp.

Up-Z-Dazy -- Funk Manufacturing Co.

Wellmaster Pipe & Supply Inc.

Rig Support Trucks, Water Trucks

Ackerman International Corp.

Flatwater Fleet Inc.

Wellmaster Pipe & Supply Inc.

Rope, Safety

American Granby Inc.

APSCO Inc.

Campbell Manufacturing Inc.

Maass Mikdwest

Merrill

Simmons Manufacturing Co.

Waterline Envirotech Ltd.

Wellmaster Pipe & Supply Inc.

Rope, Wire

Boshart Industries Inc.

Trident Tool Inc.

Wellmaster Pipe & Supply Inc.

Rotary Bits, Cone and Drag

Ackerman International Corp.

Christensen Products

Diedrich Drill Inc.

Drillers Supply Inc.

Givens International Sales

Mill Machine Co.

Star Iron Works Inc.

Trident Tool Inc.

Venture Drilling Supply

Wellmaster Pipe & Supply Inc.

Rotary Drill Collars

Ackerman International Corp.

GEFCO -- The George E. Failing Co.

Givens International Sales

Hacker Industries

LTA Corp.

Mills Machine Co.

Star Iron Works Inc.

Venture Drilling Supply

Wellmaster Pipe & Supply Inc.

Rotary Drilling Rigs

Ackerman International Corp.

Christensen Products

Davey Drill Division of Davey Kent Inc.

Deeprock Manufacturing

Foremost Mobile

GEFCO -- The George E. Failing Co.

Givens International Sales

Gus Pech Mfg. Co. Inc.

Mid America Drilling Equipment Inc.

Schramm Inc.

SIMCO Drilling Equipment Inc.

Sun Machinery Corp.

Walker-Neer Corp.

Wellmaster Pipe & Supply Inc.

Rotary Drilling Rigs, Reverse Type

Ackerman International Corp.

Christensen Products

Davey Drill Division of Davey Kent Inc.

Drillers Supply Inc.

Foremost Mobile

GEFCO -- The George E. Failing Co.

Givens International Sales

Gus Pech Mfg. Co. Inc.

Schramm Inc.

Sun Machinery Corp.

Walker-Neer Corp.

Wellmaster Pipe & Supply Inc.

Rotary Hammer Bits

Ackerman International Corp.

Drillers Supply Inc.

Foremost Mobile

Givens International Sales

Mills Machine Co.

Sun Machinery Corp.

Trident Tool Inc.

Rotary Hammers

Ackerman International Corp.

AMS Inc.

Foremost Mobile

Givens International Sales

Mid America Drilling Equipment Inc.

Mills Machine Co.

Trident Tool Inc.

Rotary Kellys

Ackerman International Corp.

GEFCO -- The George E. Failing Co.

Givens International Sales

Hacker Industries

Mills Machine Co.

Star Iron Works Inc.

Trident Tool Inc.

Rotary Subs

Ackerman International Corp.

Diedrich Drill Inc.

Foremost Mobile

GEFCO -- The George E. Failing Co.

Givens International Sales

Hacker Industries

LTA Corp.

Mills Machine Co.

Parkersburg Tool Co.

Star Iron Works Inc.

Trident Tool Inc.

Rotary Tables

Ackerman International Corp.

Amarillo Gear Co.

Davey Drill Division of Davey Kent Inc.

Foremost Mobile

GEFCO -- The George E. Failing Co.

Hacker Industries

Rubber Hose Clamps and Fittings

American Granby Inc.

APSCO Inc.

Campbell Manufacturing Inc.

LTA Corp.

Maass Midwest

Service and Repair Rigs

Diedrich Drill Inc.

Flatwater Fleet Inc.

GEFCO -- The George E. Failing Co.

Hacker Industries

Solids Separation Equipment

Double Life Corp. (The)

Stabilizers

Ackerman International Corp.

APSCO Inc.

Campbell Manufacturing Inc.

Givens International Sales

Hacker Industries

LTA Corp.

Mill Machine Co.

Star Iron Works Inc.

Trident Tool Inc.

Venture Drilling Supply

Swivels

Ackerman International Corp.

Drillers Supply Inc.

Foremost Mobile

GEFCO -- The George E. Failing Co.

Givens International Sales

Hacker Industries

LTA Corp.

Star Iron Works Inc.

Trident Tool Inc.

Venture Drilling Supply

Wellmaster Pipe & Supply Inc.

Tool Wrenches and Tongs

Ackerman International Corp.

APSCO Inc.

Drillers Supply Inc.

GEFCO -- The George E. Failing Co.

Givens International Sales

Mills Machine Co.

Parkersburg Tool Co.

Scorpion

Trident Tool Inc.

Wellmaster Pipe & Supply Inc.

Underreamers

GEFCO -- The George E. Failing Co.

Givens International Sales

Hacker Industries

Mills Machine Co.

Numa

Parkersburg Tool Co.

Trident Tool Inc.

Water Level Measuring Equipment

APSCO Inc.

Ardan Enterprises

Campbell Manufacturing Inc.

Environmental Manufacturing Inc.

Geokon Inc.

Geotech Environmental Equipment

Givens International Sales

Keck Instruments Inc.

Monoflex, Div. of Campbell Mfg.

National Well Supplies Co. Inc.

Powers Electric Products Co.

QED Environmental Systems Inc.

Roctest Inc.

RST Instruments Ltd.

SA Electronics Inc.

Solinst Canada Ltd.

Star Iron Works Inc.

Stevens Water Monitoring Systems

Testwell Instruments

Trident Tool Inc.

Waterline Envirotech Ltd.

Wellmaster Pipe & Supply Inc.

Well Gravels

American Metals Corp.

APSCO Inc.

Atlantic Screen & Mfg. Inc.

Buffalo Well Products

Colorado Silica Sand Inc.

National Well Supplies Co. Inc.

Wellmaster Pipe & Supply Inc.

Well Probes

AMS Inc.

Buffalo Well Products

Campbell Manufacturing Inc.

Enviro Products Inc.

QED Environmental Systems Inc.

Roctest Inc.

Solinst Canada Ltd.

Well Screens and Points, Metal

American Granby Inc.

AMS Inc.

APSCO Inc.

Boart Longyear Co.

Buffalo Well Products

Campbell Manufacturing Inc.

Cook Screen Technologies Inc.

Diedrich Drill Inc.

Environmental Manufacturing Inc.

Flomatic Valves

Givens International Sales

Merrill

Nagaoka USA

National Well Supplies Co. Inc.

Roscoe Moss Co.

Simmons Manufacturing Co.

Solinst Canada Ltd.

Stevens Sales Inc.

Titan Industries Inc.

U.S. Filter/Johnson Screens

Wellmaster Pipe & Supply Inc.

Western Well Screen Mfg., Div. MWM Indus.

Well Screens and Points, Nonmetal

Aardvark Corp.

APSCO Inc.

Atlantic Screen & Mfg. Inc.

Bedrock Enterprises Inc.

Boart Longyear Co.

Buffalo Well Products

Campbell Manufacturing Inc.

CertainTeed Corp., Pipe & Plastics Group

Diedrich Drill Inc.

Environmental Manufacturing Inc.

Flomatic Valves

Givens International Sales

Jayco Screen Inc.

Jet Stream Plastic Pipe Co.

Johnson Well Equipment Inc.

Kilman Electriloc Inc.

Monoflex, Div. of Campbell Mfg.

National Well Supplies Co. Inc.

Roscoe Moss Co.

RST Instruments Ltd.

Solinst Canada Ltd.

TIMCO Manufacturing Inc.

Titan Industries Inc.

Western Well Screen Mfg., Div. MWM Indus.

Well Screens, Fiberglass

Buffalo Well Products

Burgess Well Co. Inc.

Campbell Manufacturing Inc.

ENCO. EMC

Givens International Sales

Well Seal Vents

American Granby Inc.

APSCO Inc.

Atlantic Screen & Mfg. Inc.

Baker Mfg. Co./ Monitor Division

Buffalo Well Products

Campbell Manufacturing Inc.

Maass Midwest

Simmons Manufacturing Co.

Winches, Hoists, and Cranes

Ackerman International Corp.

AMS Inc.

Bloom Manufacturing Inc.

Braden Carco Gearmatic -- PACCAR Winch Division

Flatwater Fleet Inc.

Givens International Sales

Pullmaster Winch Corp.

Smeal Manufacturing Co.

TIMCO Manufacturing Inc.

Wellmaster Pipe & Supply Inc.