GBU-39 Small Diameter Bomb

The GBU-39/B Small Diameter Bomb (SDB) is a 250-pound (110 kg) precision-guided glide bomb that is intended to allow aircraft to carry a greater number of smaller, more accurate bombs. Most US Air Force aircraft will be able to carry (using the BRU-61/A rack) a pack of four SDBs in place of a single 2,000-pound (910 kg) Mark 84 bomb.