This is a DEVEPHC4548 3/8" Fluid Hose Connector. Quick universal coupler can be used with most US & european couplers. Safety lock reduces the risk of possible injury or damage due to accidental air line disconnect. Once the coupler is engaged, turn the regulator ring to lock & regulate the air flow. Built-in air flow regulator opens up 85 cfm of air. Pressure release, no whiplash when disconnecting tools.