The nominal weight of the bomb is 1,000lb (454kg), although its actual weight varies between 985lb (447kg) and 1,030lb (468kg), depending on fuze options, and fin configuration. The Mk 83 is a streamlined steel casing containing 445lb (202kg) of Tritonal high explosive. When filled with PBXN-109 thermally insensitive explosive, the bomb is designated BLU-110.