Asahi/America 
Asahi/America is the leading manufacturer of corrosion-resistant thermoplastic fluid handling products, including valves, actuators, pipe and fittings. Our products have been used in the field for over four decades. Known for quality construction and dependability, Asahi/America’s valves, actuators and piping systems provide dependable cost effective solutions to any fluid handling concern.
Orion Fittings
Designs and manufactures a full line of polypropylene and polyvinylidene fluoride (PVDF) acid waste, pure water, and neutralization systems. Offers complete drainage systems including pipe, fittings, traps, dilution tanks, neutralization basins, and sinks.
REHAU
REHAU crosslinked polyethylene pipes are a flexible, durable and
cost-effective alternative to copper and other polymers. For delivery of
drinking water from the water main to the tap, REHAU offers MUNICIPEX®
water service line and REHAU PEX plumbing pipe. Our innovative FIREPEX®
residential fire protection system is paving the way for more universal
use of fire sprinklers in new home construction.
Watts 
Since 1874 a leading manufacturer of water safety & flow control products, backflow prevention devices, water quality & conditioning products, specification drainage products, brass & tubular products, control valves, potable PEX plumbing products, Quick-Connect Push Fit Solutions, and Custom OEM Products.
Zurn Plumbing Products Group
A family of specialty companies dedicated to producing "engineered" roof-to-basement water and water drainage controls for the residential, commercial, industrial and institutional building markets.
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See also: 22 1057 - Corrosion Resistant Piping, Valves and Fittings for more corrosive resistance than PVC - FRPP, PVDF, etc.
Asahi/America
Asahi/America is the leading manufacturer of corrosion-resistant thermoplastic fluid handling products, including valves, actuators, pipe and fittings. Our products have been used in the field for over four decades. Known for quality construction and dependability, Asahi/America’s valves, actuators and piping systems provide dependable cost effective solutions to any fluid handling concern.
Orion Fittings
Designs and manufactures a full line of polypropylene and polyvinylidene fluoride (PVDF) acid waste, pure water, and neutralization systems. Offers complete drainage systems including pipe, fittings, traps, dilution tanks, neutralization basins, and sinks.
REHAU
REHAU crosslinked polyethylene pipes are a flexible, durable and
cost-effective alternative to copper and other polymers. For delivery of
drinking water from the water main to the tap, REHAU offers MUNICIPEX®
water service line and REHAU PEX plumbing pipe. Our innovative FIREPEX®
residential fire protection system is paving the way for more universal
use of fire sprinklers in new home construction.
Watts
Since 1874 a leading manufacturer of water safety & flow control products, backflow prevention devices, water quality & conditioning products, specification drainage products, brass & tubular products, control valves, potable PEX plumbing products, Quick-Connect Push Fit Solutions, and Custom OEM Products.
Zurn Plumbing Products Group
A family of specialty companies dedicated to producing "engineered" roof-to-basement water and water drainage controls for the residential, commercial, industrial and institutional building markets.