ABUS 83 Series Chrome plated brass body heavy-duty padlock with a through hardened steel alloy NanoProtect Chrome Plated shackle (helping to make rusty shackles a thing of the past). Pin tumbler cylinder rust free components with anti-pick mushroom pins, resists picking. 'NanoProtect' Chrome Plating, Hardened steel & through hardened steel alloy shackles get the most effective protection available, where smallest nano particles close the smallest gaps found in the normal chrome plating 'making rusty shackles a thing of the past'. 1,000 hours salt bath test, the equivalent of 40 years in a harsh environment proves the durability of the new 'NanoProtect' process. The 83 series range of padlocks offer a medium to high level of security, with the ability to offer various levels of security within one keying system and is suitable for internal or external use.