... 2.5", 3", 3.5", 4", 6" 2.Connection: brass, stainless steel,plastic 3.Dial and pointer: aluminum ... 2", 4"(2)Case:304 stainless steel(3)Window: glass, polycarbonate.(4)Bounden tube: 316 stainless steel, brass(5)Connection: stainless steel, brass ... (6)Connection size: 1 / 8" 1/4 ...