ADVANCED DRAINAGE SYSTEMS INC.
ALIAXIS GROUP S.A./N.V.
AMANCO
AMIANTIT GROUP
ASAHI/AMERICA
CAN CLAY
CHARTER PLASTICS
ELECTROSTEEL CASTINGS LTD.
ENDOT INDUSTRIES INC.
ERA/YONGGAO CO. LTD.
FUTURE PIPE INDUSTRIES (FPI)
GF PIPING SYSTEMS
HOBAS
JINDAL SAW LTD.
JM EAGLE
KUBOTA
LESSO
MCWANE
NATIONAL PIPE & PLASTICS INC.
NORTH AMERICAN PIPE CORP.
NORTHERN PIPE PRODUCTS INC.
NORTHWEST PIPE CO.
PERFORMANCE PIPE
SAINT-GOBAIN PAM
SEKISUI CHEMICAL
U.S. PIPE
WATER TRANSMISSION GROUP (WTG)
WAVIN
WIENERBERGER AG
XINXING