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 times. Adjust the screw by using the hexangular key to fit the frame thickness. Fit for track heights more than 15mm/ 0.59 inch,track thickness no 16mm/ 0.63 inch. Wide usage: Can be easily 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.