Connect and Disconnect Tubing without Tools-Meets FDA standards & NSF listed. O-ring/collet design. Type 302 S.S. teeth for extra gripping power. Acetal bodies, nitrile o-rings, and acetal/stainless steel collets meet requirements for food grade and high-purity applications. Temperature from 33° to 158°F. 5/32" - 5/16" will withstand 230 PSI @ 73°F. 3/8" - 1/2" will withstand 150 PSI @ 73°F. Will withstand a full vacuum. Use fittings with polypropylene, polyethylene, and other rigid tubings. Special adapters (tube-to-hose stems and elbows) let you use soft tubing such as Tygon (R) or silicone. Create rotating swivel connections by connecting special stem adapters with male pipe threads together. Light gray color. Acetal-Celcon.