Material: Made of high quality material, able to withstand higher pressure, not easy to damage. Excellent Safety: High quality choke cable for added safety, health and safety at home and baby / child safety. Easy to Install: Made of steel wire which measures 19cm long, comes with self-drilling screws and wrenches, just a screwdriver or drill to install. Widely Used: Ideal for PVC, aluminum, wood, composite doors and windows. Use on double hung, casement and slide windows; balcony doors, guest bedroom doors, etc. Special limiting design: It provides 19cm of restriction and fresh air, and the window can be opened fully once the cable is pulled out for one end using the wrench. New shape, smooth line: You can bend it at will, cable distance up to 18.5 cm. Unique locking core, greatly increased the security of the door lock.