China Lesso Group Holdings Ltd. (China)
Astral Polytechnik Limited (India)
Polypipe Plc (UK)
Advanced Drainage Systems Inc. (US)
Amanco (Brazil)
National Pipe and Plastics Inc. (US)
JM Eagle Inc (US)
NAPCO (US)
Finolex Industries Ltd (India)
and IPEX Inc (Canada) among others