Ventilation and safetyThis window restrictor not only meeting the function of ventilation but also protects the children in your house, it prevents babies from pinching their hands by opening or closing the window without adult supervision; Prevents babies from climbing up the window; It is not only effective for babies, but also effective for pets. Adjustable and Longer: window restrictors are adjustable. Two different opening sizes are available, 5.12 inches (13 cm) and 6.30 inches (16 cm). Just turn the knob easily to change the opening size. Universal and Multiple UseOur baby safety locks have a wide range of application, Not only suitable for most type of Windows such as (inner opening window, outer opening window, sliding window), but also suitable for doors, washing machines, etc. It can protect children's little fingers from being pinched between the door and the wall; prevent children from getting into the washing machine. Two installation methodsThere are two installation methods: one is adhesive installation, super simple; The second is screw installation, super durable. In addition, screws and adhesives can be combined to achieve the best installation results. Easy Operation: Just press and hold the side button while sliding the middle button down, unlock completed. Then the window can be opened completely as usual. If you want to lock it, just place the ring in place and sliding the middle button up. It is easy for adults to use but difficult for babies to open.