Controlling access to homes, rental properties, or construction sites has never been easier or more convenient. If you are a real estate agent, property manager, or Airbnb host, the Master Lock 5420D Set Your Own Combination Portable Lock Box with Universal Shackle is the only integrated lock box product on the market that features a universal shackle for secure use on most types of door hardware. While other lock box models can be easily removed from lever style handles, the Universal Shackle Lock Box cinches tightly and securely to most door hardware styles. The 5420D also fits securely to knob and handle hardware styles providing versatility for those who need to share keys, key fobs and access cards. Features: Universal shackle cinches lock box tightly and securely to most lever, ball, biscuit, and tulip door knob styles Key lock box for secure storage of up to 6 keys; large internal capacity also allows for storage of key fobs and access cards Set your own 4 digit combination lock box for easy combination recall; set and reset your combination allowing thousands of personalized combination code options For indoor and outdoor use; vinyl coated shackle and molded bumper prevent scratching, metal body construction for durability, weather cover protects combination dials from outdoor elements 2-7/8 in. W lock body; 3/8 in. Dia shackle with 1-3/4 in. maximum length, 3/4 in. minimum length, 1-13/32 in. W; internal dimensions: 4-3/16 in. H, 2-3/8 in. W, 1 in. D