The All Terrain Tactical Enforcer (AT-TE), sometimes simply called a Republic tank, was a multipurpose military ground walker used by the Galactic Republic during the Clone Wars. They were eventually phased out of service and replaced by the newer All Terrain Armored Transport.
After the Clone Wars, Rex along with Wolffe and Gregor retired from service and lived on a Modified AT-TE walker where they traveled around the outskirts of Seelos to occasionally hunt down Joopas for food and later used it in a skirmish against three AT-ATs led by Agent Kallus in defense of the Ghost crew.
The AT-TE boasted 6 legs that could be magnetized, and six anti-personnel laser cannon turrets located along the body of the walker. It also featured a heavy projectile cannon on top. The interior was also pressurized to contain a breathable atmosphere when in space or inhospitable environments.