Abus 83 series chrome plated brass open shackle heavy duty padlock with a nano protect chrome plated shackle the nano protect coating is made up from hardened steel through hardened steel alloy shackles to provide 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 this has been tested for 1000 hours in a salt bath the equivalent of 40 years in a harsh environment proving the