PEX potable water tubing combo contains 1x half (1/2) in. x 100 ft. red 1x half (1/2) in. x 100 ft. Blue 1 in. x 3/4 in. x 100 ft. red 1x 3/4 in. x 100 ft. Blue PEX potable water tubing (non-barrier PEX tubing) is used for residential and light commercial hot and cold-water plumbing applications. Tubing is marked every 5 ft. with length, ASTM standards, approvals, certifications, pressure ratings and other technical information. PPWRB1234100 PEX tubing is a strong and flexible cross-linked polyethylene tubing with superior temperature and pressure ratings that is useful for plumbing project in commercial and residential hydronic radiant heating applications. The tubing system works with cinch clamps seal for optimal leak free water flow connections. PEX-B is made using a silane or "moisture cure" method of crosslinking, where links between the molecules of the HDPE polymer are formed after the extrusion process using a catalyst and by exposing PEX tubing to water (steam bath). Tubing conforms to NSF, UPC, ASTM and Warnock Hersey standards. Warranty: industry standard, 25-years manufacturer's warranty. Applications: PEX tubing without oxygen barrier is common for the following applications. Plumbing applications (hot and cold water) loop radiant heating applications. Color: Red/ Blue. Material: Cross-Linked Polyethylene (PEX).