Rustproof steel padlock with 4-pin tumbler locking mechanism. Includes two brass keys. 31-8864 is 1-9/16" inside; shackle dimensions are: 9/32" diameter, 3/4" vertical, and 5/8" horizontal clearance. 31-8865 is 1-1/8" wide; shackle dimensions are: 3/16" diameter, 9/16" vertical and 1/2" horizontal clearance. 1 per card.