- Type: Gun-type fission bomb
- Length: 10 feet (3 meters)
- Diameter: 28 inches (71 cm)
- Weight: 9,700 pounds (4,400 kg)
- Core: Uranium-235
- Yield: Approximately 15 kilotons of TNT
- Impact Location: Hiroshima, Japan
- Mechanism: Used conventional explosives to fire a sub-critical mass of uranium-235 into another, achieving critical mass and initiating a nuclear chain reaction.