The Machbet (Hebrew: מחבט, meaning "racquet") is an Israeli upgrade of the M163 self-propelled automatic anti-aircraft gun, based in turn on the M113 armored personnel carrier. In addition to the 20 mm M61 Vulcan rotary cannon it is armed with four FIM-92 Stinger surface-to-air missile launch tubes. The Machbet comes equipped with an upgraded tracking system and can establish a datalink with an external radar. The vehicle carries 1,800 rounds of 20 mm ammunition and 8 Stinger missiles.The Israeli Aircraft Industries (IAI) developed the Machbet in the mid 1990s. It had undergone testing in the IDF in 1997 and entered operational service in 1998. Pending on budget issues, the IAF is planning to convert all its Hovets to the newer Machbet configuration.