Application: Window security locks can be used on aluminum, wood, and vinyl windows, suitable for vertical and horizontal sliding windows, singlehung windows, and doublehung windows or doors. They are common locks for homes, public buildings, etc. that require sliding windows Advantage: The lock is made of aluminum alloy, which is hard and not easy to break, wearresistant, corrosionresistant, rustresistant, and durable Note: Before ordering, please refer to the picture for size and compare with your needs Adjustable: The direction can be adjusted left and right, and you can choose according to your different needs. It is designed for installation on the left sides of your window Package Includes: 1 Set casement window handle lock with 4 pcs Screws. The installation operation is simple. Use an electric drill to drill a hole on the side of the window, and then tighten the screws with a Phillips screwdriver to lock the metal sash lock