1. Smooth to use: when you insert and use the key, it rotates smoothly and without jamming, so you can open and close the lock cylinder. 2. The lock cylinder fits most types of doors, including wooden doors, metal doors, PVC doors, interior doors, front doors, and most doors with keyholes. 3. It is a good choice for train stations, toilets, basements, interior doors, front doors, old schools, hostels, and kitchens. 4. Features unique antibump protection that does not use catch pins. This ensures that turning the cylinder wrench is particularly smooth while blocking the access of impact keys. 5. The drillresistant function is designed to ensure all moving pins are made of nickelplated hardened steel for longlasting durability. 6. With careful safety design, this lock offers antipick, antibump, and antidrill protection. 7. This door lock is suitable for all types of doors, including wood, metal, patio doors, and composite doors. It can be used as both a lock and a replacement lock.