The T-80 appeared as production model in 1984 and is manufactured by Transmash in Omsk. It has the basic features of the T-64 series (including the 125mm smoothbore gun with autoloader). The T-80 is also very similar in appearance to the T-72, but compared with the standard T-72, the T-80 has side skirts attached and twelve turret-mounted grenade launchers with seven on the left side and five on the right side. The T-80 was the first Soviet tank to be powered by a gas-turbine. To extend the operational range of the T-80, additional fuel tanks can be mounted at the rear of the hull, which can be quickly jettisoned in battle. A large circular container mounted on the turret rear carries the snorkels for deep fording operations. The T-80 was also the first production Soviet tank to be equipped with a laser range finder and a ballistic computer system. The T-80 uses the same 125-mm gun and ammunition system as the T-72. The BK-29 round, with a hard penetrator in the nose is designed for use against reactive armor. The BK-27 HEAT round has a triple-shaped charge warhead and 50 mm more penetration. Another round, called Ainet, is specially designed to defeat targets by firing fragmentation patterns forward and radially. The detonation points are based on computer calculated settings from the laser range-finder. Targets for the Ainet rounds are helicopters and dug in or defilading ground threats. The T-80 is fitted with explosive reactive armor (ERA) and virtually immune over its frontal arc to penetration from all current NATO ATGMs which rely on a HEAT warhead to penetrate armor. All turret sides of the T-80 are also fitted with ERA panels and also the forward part of the turret roof to provide protection against top attack weapons. But this explosive reactive armor does not provide any added protection when attacked by APDS or APFSDS rounds.