The tanks were specifically modified for use by the Dark Acolytes of the Confederacy of Independent Systems, led by Count Dooku. Each of these craft were armed with a supercharged blaster cannon and a missile launcher. Though effective in one-on-one attacks, Dooku insisted that they travel in groups of three for improved effectiveness.
In 22 BBY, after the Jedi rescued Jedi Knight Obi-Wan Kenobi, his Padawan Anakin Skywalker, and Republic Senator Padmé Amidala during the Battle of Geonosis, three Dark Acolytes attacked Jedi Master Mace Windu's TX-130 Saber-class fighter tank, as he made his way to Dooku's hangar to confront the Sith Lord. They dealt heavy damage to his tank, but he managed to penetrate their shields, overpowering and destroying them.