The U.S. Army and Marine Corps are fielding new tracked vehicles – the Joint Assault Bridge (JAB) and the Assault Breacher Vehicles (ABV) – intended to improve battlefield mobility. The ABV is designed to breach minefields and complex obstacles and provide a deliberate and in-stride breaching capability for the Marine Air Grounds Task Force and the Army Heavy Brigade Combat Team. The JAB has atop it a 60-foot bridge that can be launched when other tracked vehicles like the M1 main battle tank need to cross wet or dry terrain. ABV and JAB vehicles were introduced as prototypes designed for the Marine Corps and Army. The hulls for both vehicles utilize refurbished M1 tanks. ABV is already in production with 30 vehicles fielded with Marine units for training purposes. Production of the JAB has just begun with five vehicles completed for design evaluation.