Israeli air strikes with BLU-109 concrete-piercing bombs. Israeli aircraft began using BLU-109/B bombs to attack Hamas underground bunkers and tunnels. The American bunker-busting bomb BLU-109/B weighs 907 kilograms and has a warhead weighing 240 kilograms, consisting of tritonal. The bomb is capable of breaking through reinforced concrete floors up to 1.8 meters thick. Accurate targeting can be provided by JDAM or Paveway systems; with the help of these guidance systems, the aerial bomb becomes controllable.