Koolance (patent-pending) quick disconnect no-spill coupling with automatic shutoff. G 1/4 BSPP threaded female fitting for screwing directly into a water block or other component. It will only fit a Koolance QD3 male quick disconnect.After pulling the ring on the female QDC side, the quick-disconnect fittings will separate. Liquid on both sides will be automatically obstructed with approximately 0.2mL freed. Fittings are chrome-plated brass. Maximum operating pressure is 2kgf/cm2 (28.5 psi) @ 25C. Maximum operating temperature is 100C (212F).