T-204 Hayes main battle tank

The T-204 Hayes main battle tank was a tank used by Starfleet ground forces in the early 25th century. 

History
In 2410 the USS Bajor carried a complement of T-204 tanks into the Delta Quadrant as part of the 103rd Expeditionary Force. Ten of these tanks were deployed against the Vaadwaur on Kobali Prime, and two were destroyed by enemy fire. ("Tinker, Golfer, Doctor, Trill", "Last Rights")

During the Iconian invasion of New Romulus later that year, High Admiral D'trel lamented that the Bajor apparently had not retained any of the tanks in question.

Technical data
The T-204 measured 10 meters long, 4 meters wide, and weighed 24 metric tons. The tank was heavily armed, with a 120 millimeter smoothbore coilgun capable of putting a bunker-buster round through eight meters of ferrocrete, as well as sponson-mounted dual Type 5 phasers and a Type 4 phaser assault minigun on the turret. Power was supplied by a miniature fusion reactor much like that of a Type-10 shuttlecraft. ("Last Rights")

Background
mentioned in the author's notes for "Last Rights" that the T-204's design was meant to evoke a combination of a current-generation main battle tank such as the or, and a Leman Russ from . The name was a combination of American and Russian tank nomenclature, with "Hayes" referring to MACO Major J. Hayes of.