Apply to windows and doors, make sure the track heights more than 1.2 cm/ 0.47 inches, track thickness no more than 1.6 cm/ 0.63 inches, suitable for most windows and doors. Convenient to install, each lock is equipped with key, the key slowly through the hole, just holding on the track by key control, no additional installation tools. Durable material, it is strong, solid and sturdy, workmanship, aluminum alloy frame and stainless steel screws that can be reused many times. Features - ColorAssorted Color - Material: Aluminum Alloy - Size: 3.5 x 5 x 5cm - Durable material, it is strong, solid and sturdy, workmanship, aluminum alloy frame and stainless steel screws that can be reused many times. - Convenient to install, each lock is equipped with key, the key slowly through the hole, just holding on the track by key control, no additional installation tools. - Apply to windows and doors, make sure the track heights more than 1.2 cm/ 0.47 inches, track thickness no more than 1.6 cm/ 0.63 inches, suitable for most windows and doors. - Can be easily applied to most environments. By keeping the windows partially open and closed, it's burglar-proof and can prevent children from falling and protect the safety of their families while improving air circulation. Package list: 10 x Window Locks