is 780 mm, its mass 9 kg. On 6 May 2014, the U.S. Army announced that it awarded a US$12 million contract to defense contractor General Dynamics for the demilitarization and disposal of 78,000 aging depleted-uranium (DU) tank rounds as newer rounds are added to the U.S. war reserves. The contract includes M829A1 and M829A2 rounds. M829A3 With the Soviet creation of the Kontakt-5 Explosive Reactive Amour (ERA), the M829A2 was the US immediate response, developed in part to take on this new ERA type. The M829A3 is a further improvement, designed to defeat any future armor protection methods, like 'Kaktus' ERA, which was seen on the now canceled prototype tank, the Object 640 "Chiorny Oriol" (Black Eagle) (sometimes falsely named the T-80UM-2). It completed type classification standard in March 2003. Very little is publicly known about the round, perhaps due to export restrictions (see International Traffic in Arms Regulations (ITAR)). The M829A3 uses a more efficient propellant, RPD-380, boosting its muzzle velocity. The M829A3 round has a total mass of and length of . It uses of RPD-380 stick propellant, accelerating a depleted-uranium rod penetrator, which has a penetration value and a muzzle velocity of . From patents submitted by Orbital ATK, the penetrator is composed of two sections, an approximately steel tip and the rest composed of depleted uranium. The penetrator diameter was also increased from to , improving penetrator strength by 67%. This suggests the steel tip is used to defeat the ERA, with the depleted uranium used to complete the penetration through the vehicle's passive armor. The resulting muzzle energy is . The sabot is of composite material. This variant is unofficially referred to by Abrams tank crews as the "super sabot". Although the M829A3 fired from the 44-caliber M256 gun has a lower muzzle velocity than 120 mm shells fired from the Rheinmetall 55-caliber gun barrel or Russian 2A46 125 mm gun ammunition, it uses a larger penetrator with increased mass to increase imparted kinetic energy. M829A4 The A4 (formerly E4) variant was under development by General Dynamics Ordnance & Tactical Systems and Alliant Techsystems (ATK) until ATK received a $77 million, three-year contract on 11 July 2011 to develop and qualify the M829A4 Advanced Kinetic Energy (AKE) round for the U.S. Army's M1A2 SEP (System Enhancement Package) Abrams MBT. The M829A4 is a fifth-generation APFSDS-T cartridge using a depleted-uranium penetrator with a three-petal composite