ADJUSTABLE WINDOW GAP SIZE --- With the SAFELON Window Limiter, you can choose from two different window opening sizes: 3.62""""(9.2cm) and 5.31""""(13.5cm). The size of the adjustable window slot can meet the daily ventilation requirements and the needs of more customers. Why you need it --- The window lock is strong enough because it is made of polyamide. Don't hesitate, it can prevent children from pinching their fingers when playing with the window, prevent children from falling out of the window, etc. Not only for babies, but also for pets. Easy to lock and unlock --- Press the double button to unlock, the window can be opened or closed freely. No keys or other parts were lost after installing the lock. Adjust the window gap by pressing and holding the slider button on the stile and pushing or pulling the window. It's easy for adults to use, but difficult for babies. Easy to install and tips --- SAFELON window restrictor provides tape and screws for customer installation. With tape, it holds less than 58 lbs (best after 24 hours). Please select the appropriate installation method according to actual needs. Wide range of applications --- for inward-opening windows and outward-opening windows. Suitable for most windows on the market.