Honeywell International
Hot Box
Hubbell Electric Heater Co.
IMCOA
IMI Cash Acme
Inline Industries
In-Sink-Erator
IPS Corporation
ITT A-C Pump
ITT Engineered Valves
ITT Jabsco
Jacuzzi Inc.
Jay R. Smith
Jefferson Union
Johnson Controls
Jomar
Knaak Mfg. Co.
Knauf Fiberglass
LA-CO Industries
Ladish Co.
Laing Thermotech
Landis & Gyr
Lasco Fluid Distribution Products
Lawler Manufacturing
Leonard Valve
Liberty Pumps, Inc.
Little Giant Pump Company
LMI - Milton Roy
Lubrizol
Marquest Scientific
Maxitrol
McDonnell & Miller
McGill AirFlow Corp
Merit Brass Company
Mestek, Inc.
Mill-Rose Company
Milwaukee Electric Tool Corp.
Mission Rubber Co.
Moen Faucet
Mueller Steam Specialty
Myson Water Heaters
Neptune
Nesbitt
Nibco Inc.
NuTone
Oatey
Orion Fittings Inc.
Pacific Echo
Parker Hannifin Corp.
Peerless Heater Company
PEF Industries
PlastOmatic
Porcher
PowerTwist Plus
Precision Digital
P-T Coupling Company
Quality Controls
Reading Tube
Rectorseal 
Red-White Valve Corp.
Ridgid Tool Company
Robert Mfg. Co.
Saint-Gobain
Sioux Chief Mfg. Co.
Sloan Flushmate
Sloan Valve Company
SMC
Spears
Spirax Sarco
Spirotherm
Sta-Rite Industries, Inc.
Stockham Valve Company
Strahman
Sunstar Heaters
SureFire
Swan
Symmons Industries
T & S Brass
Taco Pump
Titeflex Corporation
Truebro Inc.
Tunstall Associates
Tylok Fittings & Valves
Vaughn Manufacturing
Victaulic Company of America 
Ward Manufacturing
Waterfurnace International
WaterSoft
Watts Industries
Watts Radiant
WCM Industries
Weil-McLain
Wheatland Tube Company
Wilden Pumps
Williams Valves
Winters Instruments
Versa-Matic
Yarway
York
Zoeller Pump
Zonex Systems
Zurn Plumbing Products