Lock Type:Sliding Window Locks Function:protect the safety of their families while improving air circulation It is strong, solid and sturdy, exquisite workmanship,that can be reused many . Adjust the screw by using the hexangular key to fit the frame thickness. Fit for track more than 15mm/ 0.59 inch,track thickness no 16mm/ 0.63 inch. Wide usage: Can be applied to most environments; By keeping the windows partially open and closed, the burglar-proof and thieves can prevent children from falling and protect the safety of their families while improving air circulation. Weight: 148g/set colour:Yellow + silver Material:Aluminum + plastic size:Key length: 47mm/1.85inch Window lock size: 30mm x 24mm x 24mm/1.18in x 0.94in x 0.94in Package Contents: 4 x Sliding Window Locks 4 x Keys Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.