- ACO
- ADS
- American Diamond
- A.Y Macdonald Manufacturing Co
- Bingham & Taylor
- Brentwood Industries
- Capital Industries
- Cerro
- Charlotte Pipe
- Cherne Industries
- Clow
- Contech
- Cultec
- Cupolex Storm Water Management
- Diamond Plastics?
- Earth Materials LLC WBE-SBE- DBE
- Ebba Iron
- Eclipse Industries
- Fast Fabricators Inc/US Pipe
- Febco
- Fernco
- Filtrexx Silt Soxx
- Freedom Plastics/Harco
- GA Industries
- General Engineering
- General Foundries
- Harco
- Heritage Plastics
- Hot Box
- Howell
- Ikex
- Indiana Seal
- Inserta Tee
- Ipex
- JCM Industries Inc
- Kennedy Valve
- Lasco Fittings
- Lesso Pipe
- Maccaferri Gabions
- McWane Ductile
- Milliken
- Mueller- Valves/Hydrants
- Mueller- Meters AMR/AMI
- Multi Fittings
- Mutual Industries
- NDS
- National Pipe
- Neenah Foundry
- Nibco
- North American Green
- North American Pipe
- Oatey
- Oil Creek Plastics
- Pipe Conx
- Plastic Trends / Napco
- Pratt
- Propex
- Reeed Manufacturing
- Romac
- Sigma
- Silverline
- Smith Blair
- Sonoco
- Spears
- Star Pipe
- Tensar
- Tigre
- Tyler Pipe
- US Pipe
- Uponor
- US Foundry
- VAL- Matic
- Waterman
- Watts
- Wieland / Kessler
- Winfab Geotextiles