Spring loaded: spring loaded sleeve locks coupler in place, helps to the connection between your straight coupler and this coupler and preventing leakage, make the grease filling more efficient and convenient. Designed: Grease coupler is designed with , can grease hard to reach fittings in spaces, convenient for you to connect some difficult fittings, the 3 coupler design grease fittings easier Material:These coupler are made of carbon steel material, the surface is galvanized, which can prevent corrosion to the greatest extent , durable and sturdy, not easy to break,and has a service life. For use with hand-operated grease Connects to standard grease couplers,compatible with flex hose or rigid pipe Maximum operating pressure of 4, 500 Colour: Silver Material: Carbon Steel Package Contents: 1 set x coupler adapters Only the above package content, other are not included. Note: Light and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.