Why is it necessary --- Prevent babies from pinching their fingers when opening the window; prevent babies from accidentally falling out of the window. Quick installation --- No additional tools are required for installation other than 3M adhesive. SAFELON window lock can withstand a thrust of up to 30 kg (66 lbs) and has strong impact resistance. Multi-scene --- Suitable for sliding doors, sliding windows, cabinet doors, etc. One-click operation --- Slide the middle button, the wings will bounce and the window cannot move. Press the two wings to unlock, and the window will resume normal movement. Due to the large thrust of the spring, it is difficult for the baby to operate. Multi-level adjustment --- The desired window opening width can be selected by installing multiple window locks, thereby achieving multi-level adjustment.