4pcs Patio Door LocksThis is a sliding patio door safety lock, which prevents windows from being opened unintentionally, extra safety for your child and your window. Suggest the blocks be mounted high and low for maximum security, home security system upgrade. 8 Universal KeysComes with 8 universal keys, there are 4 slide locks. Each slide lock comes with 2 keys, the keys are universal. Zinc Alloy Zinc alloy copper, rust protection, durable and quality. Easy to Install Easy to install, easy to use padlocks come complete with all security accessories including stainless steel screw caps. ApplicationSuitable for most doors and swing gates or sliding, this design is very useful for homes, schools and other places for children. Features Universal locks perfect for most hinged or sliding doors and windows. Supplied with all security fixing accessories. Suggest blocks are top and bottom mounted for maximum security. Each slide lock comes with 2 keys, the keys are universal. Specifications Material: Zinc alloy + iron + copper Total length: 40mm/1.6'' Width: 37mm/1.45" Height: 19mm / 0.75'' Distance between screw holes: 30mm/1.2'' Color: White Package Included 4 x Sliding Door Locks 8 x Keys 8 x Hoods 16 x Stainless Steel Screws