Type 2 way Operation N.O. N.C. Pipe Size 1/8 1/4 3/8 1/2 3/4 1 1 1/4 1 1/2 2 3 Minimum Psi 0 1 2 5 Max Operating Psi 50 80 90 100 125 135 140 150 155 160 165 180 200 250 275 300 340 360 530 750