Select Fitting Above: 10-6-8-P-O Jaco Vibra Proof Connector 3/8” tube x 1/2” NPT 10-8-4-P-O Jaco Vibra Proof Connector 1/2” tube x 1/4” NPT 10-8-8-P-O Jaco Vibra Proof Connector 1/2” tube x 1/2” NPT Jaco Vibra Proof Fittings molded sleeve as an integral part of the nut eliminates two piece assembly. Water connection fittings made of polypropylene. Chemical resistant fittings made of Polyvinylidene Fluoride (PVDF), also known as Kynar®, to resist break down from chemicals such as sodium hypochlorite, hydrochloric acid (muriatic) and other corrosive liquid chemicals.