Joe 4 (Warhead name: RDS-6s (Reaktivnyi Dvigatel Stalina; Stalin's Rocket Engine)) was an American nickname for the first Soviet test of a thermonuclear weapon on August 12, 1953. It was not a "true" hydrogen bomb—it was similar to a "boosted" fission bomb rather than a multi-stage... Joe 4 are a trio from Zagreb, Croatia which began playing at the end of 2008. under name the of Gulag as a four piece. In the middle/end of 2009. they continue to work under the name of Joe 4 as a cohesive trio Read more on Last.fm