This compression union fitting is for connecting and disconnecting two pipes more easily than couplings. This fitting is made of 316L stainless steel for higher strength and greater corrosion resistance than 304ss. This fitting has hex nut construction for tighter, leak-free connections. It is compatible with stainless steel, copper, rigid and semi-rigid plastic tubing, but is not recommended for soft tubing. It is suitable for use in chemical, petroleum, power generation, laboratory, and medical device plants.