3/4" Poly Alloy Barb Insert x 1/2" Poly Alloy Male Pipe Thread Adapter, For Cross Link Polyethylene Tubing For Hot & Cold Water, Use With True Value #608-933 Cinch Clamp, Need Cinch Tool True Value #608-743 Or Copper Crimp Rings On Cross Link Polyethylene Pex Tubing, After Crimping You Can Immediately Test Each Fitting To Well Over 100 PSI, NSF Listed Poly Alloy Inserts, Replacement For Brass Pex Insert Fittings To Conform To California Ab1953 Low Lead & Vermont S152 Low Lead Laws.