Description Three number dialing, permanently lubricated, rust resistant inner working parts. Dial cannot be turned when shackle is under tension, safe-guarding combination. Self-locking, automatically disarranging tumblers. Nickel plated steel swivel shackle. Strong double wall construction, stainless steel outer case armors heavy wrought steel inner case. 1-7/8" wide case, 9/32" diameter shackle, and 13/16" horizontal shackle clearance.