Wirsbo hePEX features an oxygen barrier that conforms to DIN 4726 for use in closed-loop hydronic piping and radiant heating and cooling applications. The tubing is rated and listed by the Hydrostatic Stress Board of PPI at 200 deg F at 80 psi, 180 deg F at 100 psi and 73.4 deg F at 160 psi. It is compatible with Uponor ProPEX and QS-style fittings and is manufactured in full compliance to ASTM F876 and F877. It is also listed to NSF 61 for potable-water applications. Uponor Wirsbo® hePEX™ Tubing, 5/16 in Nominal Size, 0.292 in Inside Dia, 0.43 in Outside Dia, 250 ft Coil Length, 80 to 160 psi Working, 73.4 to 200 deg F, Polyethylene, White