Download coordinates as: The United States's Toggle nuclear test series[1] was a group of 28 nuclear tests conducted in 1972–1973.

These tests[note 1] followed the Operation Grommet series and preceded the Operation Arbor series.

Diamond Sculls was a horizontal line-of-sight (HLOS) nuclear test.

Its purpose was to test the radiation hardness of the LIM-49 Spartan anti-ballistic missile.

It was the largest HLOS test conducted by the United States, consisting of a 27-foot (8.2 m) diameter test chamber and a 1,900-foot (580 m) line-of-sight pipe.