Red Snow
Red Snow was a British thermonuclear weapon. Its physics package was identical to that of the United States W28 nuclear warhead used in the B28 nuclear bomb and AGM-28 Hound Dog missile, with an explosive yield of approximately 1.1 megaton.
The Red Snow warhead was developed after a September 1958 decision to adopt the US warhead for British use, following the 1958 US-UK Mutual Defence Agreement. It entered service in 1961, remaining in use until 1972, when it was replaced by the WE.177 bomb. Perhaps 150 were produced.