Locks on Stays On Wont Leak, Like no other air chuck on the market, the LockNFlates six steel jaws lock onto any Schrader valve to create a secure, hands free connection. The heavy duty construction is built to last and stand up to everyday use in even the busiest tire shops, service bays and garages. Features Revolutionary Design: Six steel jaws lock onto any Schrader valve to create a secure, hands free connection, 1/4 in NPT Thread size: Compatible with most standard air hoses, Hardened Seel Collet: Fits All Standard Schrader Valves VG8/8V1 valve threads, Rated to 150 PSI: Suitable for garage and industrial airline systems, auto and manual tire inflators, portable pressure gauges, and constant pressure systems, Heavy Duty Construction is built to last and stand up to everyday use in even the busiest tire shops, service bays, and garages. Durable, Spring Loaded TPU Seal: Inflate tires with or without the valve core in place, Available in 2 Styles: Open Flow or Closed Flow, Open Flow: Air passes through freely on or off the valve stem. For use with inflator gauges and automatic systems. Closed Flow: Must engage the tire valve for air to flow. For use directly from a compressor or air hose.If used with a multi-hose inflation kit, use Closed Flow LockNFlate Air Chucks.For use on Milwaukee, DeWalt or other battery inflators, choose an Open flow LockNFlate Air Chuck. Hands free. Leak free. Hassle free