Bofors 120 mm Automatic Gun L/46

Bofors 120 mm Automatic Gun L/46, most commonly referred to as either Bofors FAK 120 or Bofors TAK 120 depending on the configuration (field gun vs naval gun), was a Swedish liquid-cooled single-barreled 120 mm (4.7 in) caliber long-range anti-aircraft autocannon designed by Bofors during the 1950s for indigenous use and export. It was produced in two different variants during the 1950s and 1960s respectively, a field variant and a naval variant, and the latter still being in service today with the Indonesian Navy.

Source: Wikipedia — Bofors 120 mm Automatic Gun L/46 (CC BY-SA 4.0)