For use on horizontal and vertical sliding windows constructed of aluminum, vinyl, and wood Universal design allows these locks to be mounted on sliding sash where their checkrails rest flush when closed Keyed sash locks help child-proof sliding windows increasing the safety and security of the home or office Limits disengagement of locks and opening of sliding windows to key-only access Both the lock bodies and keepers have mounting holes spaced apart at 2-1/4 inch, on center