Extra Data: 1/2" Expansion Reinforcing Ring with stop allows for proper placement on non-barrier PEX tubing. The Expansion PEX Reinforcing Ring is required to make a proper connection., Complete line of complementary products, Easy installation, Expansion Reinforcing Rings are sold separately, size of the ring is determined by the size of the non-barrier PEX tubing being utilized. Expansion tool is required for installation.