- Smooth, jam-free cylinder rotation that blocks access to impact keys, delivering reliable operation. - Available in multiple sizes; choose between double lock cylinder and button lock cylinder to fit installation and safety requirements. - Easy key operation: insert the key and experience even rotation with no jam, for convenient locking and unlocking. - Nickel cylinder lock compatible with wooden, composite, and metal doors, as well as interior and front doors, and most doors with a keyhole. - Security features include anti-pick, anti-drill and anti-bump protection; unique anti-bump design without trap pins keeps bump keys out while maintaining smooth turning. - No need for costly handle upgrades or extra safety devices; improves security and ease of use of the lock cylinder. - Use scenarios: ideal for front entry doors to upgrade security without changing handles; suitable for interior doors for controlled access; fits patio, French and composite doors requiring a keyed lock. - Customer support: if you have any problems with our products, contact us and we will respond within 24 hours.