Scuba Choice Scuba Diving 27" Low Pressure Regulator Hose Fitting tensile strength: 150kgf/cm2 Working pressure: 350 psi Burst pressure: 1,500 psi Inner diameter: 1/4" (6.35mm).Outer diameter: 12.3mm. Male end thread: 3/8-24UNF Female end three: 9/16-18UNF