Koolance\'s QD series of quick release closures make it easy and convenient to break the coolant circuit by simply depressing a metal ring. This is especially necessary where hoses or water cooling components often have to be disconnected from the rest of the water cooling system. The higher the designation of the QD connections, the more massive and larger they are designed and are accordingly suitable for larger hose diameters. Two QD3 nickel-plated brass quick-release couplings are connected or disconnected (once male, once female), with Koolance developing valves that, as the name no-spill suggests, are designed to provide a degree of leakage. It should be noted, however, that 100% immediate sealing is not possible and can leak up to 0.2 ml of fluid. This quick release in new revision represents the straight version in male with a G1 / 4 inch thread in male. Technical Details:- Size: 31.1 x 20.4 mm- Material: brass, nickel plated- Colour: Black- Maximum pressure during operation: 113.8 psiConnections: - QD3: male - Connection: inch