Lock box application: For indoor and outdoor use; large internal cavity allows secure storage for multiple keys Ease of use: Resettable 4 digit combination for keyless convenience, set and reset your combination allowing thousands of personalized combination code options Durable design: Lockable key storage designed to fit over a door knob for portable use; metal body construction for durability and shutter door to protect combination dials from weather Ideal for set of keys: shackle dimensions (refer to visuals) a: 9 mm B: 37 mm C: 48 mm; exterior dimensions (H x W x D) 18.8 cm x 10.5 cm x 4.3 cm; interior dimensions (H x W x D) 10.1 cm x 6.4 cm x 3.2 cm Easy to secure and share your keys: Great solution for AirBNB and home rental; gives easy access to care takers and home workers; ideal to share keys with your family or roomates Great flexibility : portable model with shackel, can be placed on doors, barriers, portals or anywhere else; very convenient for collective ownership and rental as no need to fix it to the wall Limited lifetime warranty: If this product or any part of the product fails due to a defect in materials or workmanship at any time during the life of the product, Master Lock will, at its own discretion, repair or replace the product or part free of charge, Weight: 2.138 pounds, Manufacturer: Master Lock