The M117 is an air-dropped demolition bomb used by United States military forces. The weapon dates back to the Korean War of the early 1950s. Although it has a nominal weight of 750 pounds (340 kg) its actual weight, depending on fuse and retardation options, can be around 820 pounds (372 kg). The bomb's explosive content is typically 386 pounds (175 kg) of Tritonal or 377 pounds (171 kg) of Minol in the case of the M117A1E2 due to their higher density and detonation velocity compared to TNT. Demolition bombs rely on time delayed fuses which allow the bomb to burrow into a building or other structure before detonating. The M117 can be configured with a conical low-drag tail for medium and high-altitude deliveries or a high-drag tail fin for low-altitude drops, delaying the bombs hitting their targets ensuring fighters are out of the blast zone before detonation. The M117 was the basis for the BOLT-117, the world's first Laser-guided bomb. M117 bomb - Wikipedia