Feature: 1. Double Sided Design: The door knob lock is suitable for security locking of double sided doors such as passageways, ensuring high safety of your door and room. 2. Durable Material: The interior door knob lock is made of durable and reliable copper material, high strength and wear resistant, not easy to rust after long term use. 3. Invisible Design: The keyed entry knob lock has the invisible design, not affecting the appearance of the door board, keeping the door surface beautiful and clean. 4. Easy To Install: Keyed entry door knob lock has a installation, convenient and time saving, don't need too much tools or complicated steps. 5. Multifunctional Use: The door keyed knob lock is suitable for background walls, indoor doors and other places of the built in lock, having flexible and various application. Specification: Item Type: Door Knob Lock Material: Copper Door Thickness: Approx. 35-45mm/ 1.4-1.8in Unlocking: Double Sided Mechanical Key Unlocking Center Hole Distance: Adjustable Approx. 60mm or 70mm/2.4in or 2.8in. Package List: 1 x Lock Tongue2 x Lock Core2 x Lock Ears1 x Lock Cover Panel3 x Key6 x Screw1 x Instruction