Premium MaterialMade of aluminum alloy and stainless steel. The sliding window locks with keys are strong and durable, sure to last for a long time. Easy to InstallNo additional tools or modifications are required for installation. Apply a lock on each window, which is controlled and held with a key. Its use is simpleor intuitive for an adult but cannot be operated by young children. Smart ConstructionThese sliding door locks are strong, durable and precisely manufactured. With small but hard aluminum alloy frames and stainless steel screws. They withstand the test of time and different climates, so they can be reused many times. Adjustable StructureAdjust the stainless steel screw by using the hexangular key to fit the frame thickness. Fits for most horizontal windows, vertical windows and sliding glass doors. Family Essential Good HelperThese adjustable sliding window locks can be used to prevent burglars and thieves, and avoid falling accidents by keeping the windows opened or closed ; while protecting the safety of the family, it can also improve air circulation.