SecurityThe window handle can be used as a child lock\/anti-theft device, by locking the window in the house, it provides more protection for the child and gives more security for the parents. inward and outward opening plastic, aluminum and wooden windows and sloping windows. Installation SizeThe distance between the screw holes of the handle is 43 mm, the width of the main shaft is 7*7mm, and the length of the square shaft: 35mm; These window handles are manufactured to industry standard dimensions, so you can be assured that this handle will fit most Espag and Shoot-Bolt systems currently available. Easy Installation Each window handle is equipped with 2 screws and 2 keys for easy installation, lockable to almost any window and installs quickly and easily in a few simple steps. Different Opening MethodsThe window can be in 3 states with the handles: closed, open, tilted. The handles can be locked with a key when closed or tilted. Safety LockSimple and safe operation provides extra security, childproof window handle lock provides more protection and security in your apartment\/house. Most suitable for families with children and babies. One key can be used for all locks. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Sold by-YJL official store