The perfect timepiece for the sophisticated aviator, this Hamilton Khaki Aviation Converter Automatic Chronograph Men\'s Watch allows you to calculate critical conversions and metrics at a glance with the bi-directional, rotating slide-rule bezel. At A Glance  Presented on a brown leather strap with pin buckle fastening 44mm case size with 100m water resistance Black dial with chronograph sub dials Baton hour markers with date window at 3 o\'clock Bi-directional, rotating slide-rule bezel Converts units, such as feet to meters or miles to kilometres, and currency Scratch resistant sapphire crystal glass Powered by the H-21-Si automatic chronograph movement with its superior anti-magnetic silicon hairspring