This Yale Locks Brass Padlock has a steel shackle and 4 pin cylinder with single locking feature. Tested up to 48 hours for corrosion resistance to ensure protection against different weather conditions. Designed to protect your work or gym locker, backpack, toolbox and any other indoor valuables you want to keep secure. Specifications: Body Width: 21.4mm. Body Height: 21.8mm. Body Depth: 10mm. Shackle Diameter: 3.3mm. Shackle Height: 23.5mm. Shackle Width: 10.8mm. The Yale Locks Brass Padlocks are constructed from hard wearing boron, and are rigorously tested against corrosion. The 4 pin cylinder with single locking feature (20mm) and 5 pin cylinder with double locking feature (30 60mm). 20mm