Koolance QD3-MS10X13-BK QD3 Male Quick Disconnect No-Spill Coupling, Compression for 10mm x 13mm (3/8in x 1/2in) *Black* Koolance patented quick disconnect no-spill coupling with automatic shutoff. 10mm (3/8in) ID male straight connection with compression fitting. It will only fit a Koolance QD3 female 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.