FunctionOur Compressor Quick Coupler has a built-in valve that shuts off the air when changing tools, makes the replacement process safer and faster. SizeConnector of 1/4" BSP threaded hose: 1 female external thread connector, 1 female internal thread connector, 4 male external thread connectors, 4 male internal thread connectors. Easy to Use Simply insert the connector directly when using, and slide the snap ring all the way back after using to separate. No need for tedious operations and improve work efficiency. Sturdy and DurableHeat-treated hardened steel air line connectors with nickel-plated surface, strong and durable, rust and corrosion resistant, ensure long-term use. Wide Application These Compressor Fittings are suitable for pneumatic tools, air compressors, air hoses, etc., suitable for 1/4" BSP fittings and fittings. Reduce accidental air line disconnection when changing tools.