... coupling brass press fitting is made of brass body,EDPM seal rings,stainless steel SUS 304 sleeve and plastic ring.Brass body material can be ... CW617N, CW602N, Hpb59-1, Hpb58-2, Hpb58-3, etc;brass body superficial treatment can be ... sleeve, indeed the tube has been inserted until the end of the fitting; the other male side can connect the same thread ...