The TAR-21 (or simply Tavor) is an Israeli bullpup assault rifle chambered for 5.56×45mm NATO ammunition with a selective fire system, selecting between semi-automatic mode and full automatic fire mode. "TAR-21" stands for "Tavor Assault Rifle – 21st Century". In 2009, the MTAR-21 (Micro Tavor) was selected to become the standard issued weapon of the Israeli infantry by 2018. The TAR-21 design was created by Zalmen Shebs, with the express purpose of creating a weapon more suited to urban combat than the M16/M4 carbine. It is based on advanced ergonomics and composite materials in order to produce a more comfortable and reliable rifle. The TAR-21 is waterproof and lightweight. The weapon has a built in laser and MARS red dot sight, but the TAR-21 can also be mounted with an array of different sights such as a holographic weapon sights, night vision systems and other electronic devices.
The rifle uses a long-stroke piston system to redirect high pressure gases from rounds being fired to eject spent shells and reload new ones. The TAR-21 has ejection ports on both sides of the rifle so it can easily be reconfigured for right or left-handed shooters. However, this process requires partial disassembly, so it cannot be quickly reconfigured while the rifle is in use. The barrel features 6 grooves in a 178 mm (1 in 7 inch) or 32 calibers right hand twist rate. The IDF uses both 55-grain M193 and 62-grain M855 5.56×45mm rounds. M193 rounds will be used by regular infantrymen for better terminal effects at shorter distances, while the heavier M855 will be used by sharpshooters. The barrel has a flash suppressor similar to the one on the M16A2. The TAR-21 accepts standard STANAG magazines. It can also be mounted with the M203 grenade launcher. Its ambidextrous fire mode selector above the pistol grip has a semi-automatic mode and a fully automatic mode. The TAR-21 uses a bullpup design. Bullpup rifles are configured in a layout in which the bolt carrier group is placed behind the pistol grip; this shortens the overall length but does not sacrifice barrel length. The TAR-21 provides carbine length, but rifle muzzle velocity. It is used by the Alliance of Nations, the Axis of Empires, and the Coalition of Independent States.