The recce Viggen came in 2 variants; SH37 for maritime patrol using radar, and SF37 for photo recon at all altitudes, day or night.
These skins represent an SH and an SF from the 13th fighter wing in Norrköping, during the '80s and early '90s. They flew with the callsign 'Martin' (M being the 13th letter of the alphabet) and their respective tail numbers.
Armament-wise, they both could carry countermeasure pods and sidewinders on the 4 innermost pylons for self defense. The SH37 had a secondary role as a maritime strike aircraft and could carry 2 RB04's. In the 1990's these were upgraded to AJSH and AJSF, respectively, and became functionally the same (with some differences remaining) as the AJS37 we have in-game, though the AJSF never recieved any air to ground capability due to not having a radar.