Sash Jammers--- The window lock is made of high-quality aluminum alloy,door and window lock durable, sash locks not easy to rust, and has a white paint finish. Sash Blockers Are Designed to Provide Additional Security for Your UPVC/PVC Doors and Windows. Easy to install--- Window Door Lock Sash Jammer suitable for all kinds of doors and windows, mark the position of the installation hole with a pen before installation, choose a drill bit of about 3 mm, drill the hole at the marked position, and then fix the lock with screws. Anti-wear Pad--- window door lock Including Anti-wear Pad,sash window jammer Can Reduce Friction Between Jammer Arm and Windows, Protect Your Windows or Door from Being Scratched. Widely used----window lock It is suitable for opening doors and windows inside and outside doors and windows. You can lock or release the window sash just by twisting the interference arm.