Initially developed as the Cluster Bomb Unit-97 (CBU-97), which was unguided and quite inaccurate when released from high altitudes, it was modified and improved into the CBU-105 with the addition of GPS and tail guidance fins, which made it a very accurate Precision Guided Munition. The policy of tank-busting by the U.S. Air Force centers around this weapon, which is dropped by various platforms.