Small padlocks typically have body widths from about 30 mm to 48 mm (roughly 1-3/16 in. to 1-7/8 in.). Common sizes listed include 30 mm (1-3/16 in.), 40 mm (1-9/16 in.), and 48 mm (1-7/8 in.).
Shackle lengths for small padlocks generally range from about 0.69 inches up to 1.5 inches, covering very short to short-medium shackles for different attachment needs.
Keyed small padlocks commonly include two keys per lock. Multi-lock sets may include spare keys and are sometimes sold keyed-alike so one key opens multiple locks.
Common security features include four-pin cylinders, dual locking levers, anti-shim mechanisms, and hardened or reinforced steel shackles designed to resist picking, prying, and cutting.
The smallest luggage-style padlocks are very compact—example listings show body dimensions around 1.2 x 0.7 x 0.25 inches and describe them as only slightly larger than an AA battery.