Keyless convenience. Smooth 3-number dialing. Strong double-wall construction. Stainless steel outer case encloses heavy wrought steel inner case. Permanently lubricated rust-resistant inner working parts. The dial cannot be turned when the shackle is under tension, a safe guarding combination. Self-locking, automatically disarranging tumblers. Case: 1-7/8 Inch wide. Nickel-plated steel swivel shackle, diameter 9/32 Inch Clearances: 3/4 Inch vertical, 13/16 Inch horizontal. Combinations are different.