B83 nuclear bomb

The B83 nuclear bomb is an unguided variable-yield thermonuclear weapon developed by the United States during the late 1970s. Designed by Lawrence Livermore National Laboratory, the bomb first entered service in 1983. With a yield of up to 1.2 megatons TNT equivalent, it has been the most powerful nuclear weapon in the United States arsenal since 2011, when the B53 nuclear bomb was retired.
About 650 B83s were built. The bomb remains in service as part of the United States "Enduring Stockpile".