The DU content in various ammunition is 180 g in 20 mm projectiles, 200 g in 25 mm ones, 280 g in 30 mm, 3.5 kg in 105 mm, and 4.5 kg in 120 mm penetrators. DU was used during the mid-1990s in the U.S. to make hand grenades, and land mines, but those applications have been discontinued, according to Alliant Techsystems. The US Navy used DU in its 20 mm Phalanx CIWS guns, but switched in the late 1990s to armor-piercing tungsten.