The Master Lock 5400EC2 Set Your Own Combination Portable Lock Boxes features a 3-1/4in (83mm) wide metal body for durability. The portable design offers removable “over the knob” installation. Set your own four-digit combination for keyless convenience and increased security. The shutter door protects combination dials from weather, dirt and grime; and molded body and vinyl coated shackle prevent scratching. Includes two set your own combination lock boxes. The Limited Lifetime Warranty provides peace of mind from a brand you know and can trust.