Quick connector. Compressive strength, corrosion resistance, high performance and high reliability. Fast and easy to install, does not require any tools. Just slide back the collar and insert the fitting, then slide the collar fully back to lock in place. Enables tools and airlines to be quickly connected or disconnected. Features - Color: Silver.- Material: Iron nickel plated.- Size: 4.50 x 2.00 x 2.00cm/ 1.77 x 0.79 x 0.79 inch.- Made of heat treated hardened iron, Nickel plated finish for rust and erosion resistance.- Simple to use, just slide back the collar and insert the fitting, then slide the collar fully back to lock in place.- Spring loaded quick release couplers for use on the compressor side have a built in to shut off the air when changing between tools.- Air line hose compressor fitting connector quick release set air hose fitting tools that comply with the better standards in quality and safety.- It can realize the connection of connecting or disconnecting the pipeline without tools.Packing list: 10 x coupling