Quick connector. Compressive strength, corrosion resistance, and reliability. Fast and 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. - 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 to shut off the air when changing between tools.- hose compressor fitting connector quick release set air hose fitting tools that with the better standards in and .- It can realize the connection of connecting or disconnecting the pipeline without tools. : 10 x coupling