1 Pack Auto Door Closers There are 1 Pack punch-free door closers in the package, easy installatio, they will do not damage the wall 50,000 Tests and Strong Pull *The high-quality steel wire rope with diameter of 1.2mm has passed 50,000 times of tensile test and rebound test with strong Pull. *The black closer is 800G tension), the white one is 500G tension, suitable for doors or doors with stronger closing force. For example: screen doors, sliding double doors, invisible doors, security doors, aluminum alloy glass doors, iron doors, office doors, interior doors, kitchen and bathroom doors Automatically Close All Doors Suitable for doors, or doors with a slightly stronger closing force. Doors that open left and right, wooden and metal doors, residential and commercial doors, exterior/inner door, fire doors. Please Note: Door closers are not suitable for doors with carpet or too much friction Easy to UseThe installation method is simple and easy to operate, hole-free adhesive installation. You just stick them on the correct place and wait for 24 hours, they can be use. the closers do not need to adjust anymore, they have been adjusted well in advance Features Anti-oxidation, anti-corrosion, no rust, stable, wear-resistant, weather-proof, hydraulics, quiet, safe and reusable