Double spring structure, spring force, wider application range Door closers bring ease and security to your life, protecting your doors and locks. Simple to operate and suitable for a wide range of applications. Can be rotated with a hexagonal screwdriver to adjustment strength, regardless of left and right, complete accessories, easy to install and labor saving. Quiet; Smooth Nylon roller do not damage to the door surface, soft and silent, smooth door opening and closing Easy to install and ready to use right away, it effortlessly meets your automatic closing needs., Manufacturer: LRFNKCT