Quick Couplers Pressure Loss in PSI Flow GPM HQ-3 HQ-33 HQ-44 HQ-5 5 0.8 1.0 10 1.8 2.0 15 4.1 4.3 2.2 20 7.2 7.6 4.4 1.0 30 11.5 3.0 40 6.3 50 9.2 60 13.0 70 19.8