 In the SFU, the term refit denotes an upgrade to the systems of a starship, either in capability or in number.Each available refit was peculiar to its class of starship, but most refits added extra energy production systems, extra shield capacity, expanded firing arcs for existing weapons, as well as additional weapons.The refit for the D7, for example, upgraded the three Phaser-2s in the boom to Phaser-1s, upgraded the drone racks to Type-B, fixed the famous "glass shields" protecting the rear quarters, and added a valuable anti-drone rack (it saved phaser firepower for worthier targets).