pieces of child safety locks for windows and doors. This is a type of sliding door safety lock that prevents accidental opening of windows, extra safety for your child and the window. It is recommended that the locks be mounted at both the top and bottom for maximum safety. The home security system has been improved. 8 universal keys. Comes with 8 universal keys, 4 pieces of sliding door locks, each sliding door lock comes with 2 keys, the keys are universal. Easy to install. Easy to install the locks and convenient to use, comes with all safety fixing accessories, including stainless steel screw caps. Usage. Suitable for most hinged or sliding doors and windows. This design is very useful for homes, schools and other places where children stay. International products have separate terms, are sold from overseas and may differ from local products, including International products have separate terms, are sold from overseas and may differ from local products, including fit, age recommendations and product language, labeling or instructions. Includes fit, age recommendations and product language, labeling or instructions. This child safety device is used for most swing or sliding doors and windows. Easy to install padlock and easy to use. Comes with all safety fixing accessories, prevents accidental opening of the window and protects internal security. Universal locks perfect for most hinged or sliding doors and windows. Comes with all safety fixing accessories. Sold in a set of 4 Patio sliding locks, with keys. Suggest that the blocks be mounted at the top and bottom for maximum security. Each sliding lock comes with 2 keys, the keys are universal.