The O-ring in the thread (G, BSP, Metric thread) is FKM (Viton) material for sealing purpose. The body material of our stainless steel push in fittings can be SS304, SS316 and SS316L

The stainless steel push in fittings (Stainless Steel Push to Connect Fittings):
Thread Type: PT / R / BSPT thread, NPT thread, BSPP / G / BSP Thread and Metric Thread.