The Korean indigenous K1A1 MBT is an armament upgrade version of K1 MBT. Korea has produced about 1000 K1 MBT since 1987. The K1 has far greater firepower, armor, power plant than T-72/T-62 MBT of North Korea, but its firepower of 105mm rifle cannon is insufficient to meet the challenge of 21st century MBT. The K1A1 has 120mm smoothbore gun, the license version of M256 cannon of M1A2 MBT. The fire control system, GPTTS, is made by Texas Instrument, and provides excellent firepower accuracy. The K1A1 is developed by Hyundai Heavy Industry. The Korean Army will adopt K1A1from the year 2000.