Special Detachable Design---window restrictor have no key,so there no worry the key will lost and can't open the window. Special detachable design makes it easier to change the position of oping the window to fix the window with small distanec. No Baby Falling---Help to fix the window and meet the request of ventilation. The max distance of the opening window is 2.76"(7cm),it is much smaller than the distance which babies will fall out of the window. No Baby Open---The window lock can withstand 27kg of thrust, and 30kg of tension,no worry baby will open the window and fall. And also there's no worry of the shut of the window by strong wind. It won't damage the window or scare babies. Ageing Resistance---Install the window restrictor with Adhesive, no drill and tools need. Adhesive with strong viscous (Effect will be better after 72 hours.) and can be removed easily without any residual, no harm to the window. Strong tape resistance temperature of -30 to 90,no worry of the hot summer and the cold winter. Waterproof & Wide Application Range---PC&ABS material makes it stronger and bring longer service life. Waterproof materil and the tape let you no worry of the rainy day. The window restrictor can be used on the swinging window and the casement window.