The Window Restrictor Safety Lock is designed to restrict the opening distance of windows and doors to help reduce the risk of injury from falls. Meantime allows fresh air flow in. Suitable for most wooden, PVC and aluminium hinged, sash and sliding (horizontal or vertical) windows. Prevent babies from pinching their fingers by frequently opening and closing windows / doors without the supervision of adults; Prevent babies/toddlers from accidentally falling out of windows or getting out of the door. It is not only effective for babies, but also for pets. With our window limiter restrictor, two two different window opening sizes can be selected: 5.12 inches (13 cm) and 6.30 inches (16 cm). You can adjust the width of the door seam to suit the size of your pet according to your actual needs. Just switch the circular knob and adjust the door spacing at will. These window restrictor locks come with strong adhesive, can be fixed firmly with no drilling. All you have to do is peel off the protective film from the padlock and it can be stick directly onto the windows or doors (The effect will be better after 24 hours.) . Meanwhile, it is easy to remove with a hair dryer and will not damage the surface of the window.