Adjustable window gap size --- With the window limiter, two different window opening sizes can be chosen, 3.62"(9.2cm) and 5.31" "(13.5cm). The adjustable window space size can meet daily ventilation requirements and the needs of more customers. Why is it necessary --- The window lock is quite strong because it is made of polyamide. Don't hesitate, it can prevent children from playing windows and pinching their fingers, prevent children from falling out of windows, etc. Not only for babies but also for pets. Easy lock and unlock --- Press the double button to unlock the lock and the window can be opened or closed freely. No keys or other parts missing with the lock installed. Adjust the window gap by pressing and holding the sliding button on the post and pushing or pulling the window. Easy to use for adults but difficult for babies. Easy to install and tips --- Window limiter provides tapes and screws for customers to install. With ribbons, it can bear less than 58 LBS (the effect will be better after 24 hours). Please select the appropriate installation method based on the actual requirements. Wide range of applications --- Used for inward-opening windows and outward-opening windows. Suitable for most windows on the market.