BKA 1125 is a name for the Soviet type of river cutters from the interwar period and World War II. The total length of a single ship of this type was 22.7 meters and a width of 3.6 meters. The displacement reached 29-30 tons and the maximum speed did not exceed 18 knots. Units of this type were armed very differently, but it always consisted of a 76.2 mm gun placed in the turret of a T-28, T-35 or T-34 tank. Machine guns with the calibers of 7.62 and 12.7 mm, as well as 24-M-8 unguided missile launchers were also mounted.

The BKA 1125-type river cutters were put into service in the 1930s, and by the summer of 1941, approximately 85 units of this type were in service, along with related ships. These units were of small size, which allowed them to operate even on narrow rivers and low draft, which allowed them to operate in very shallow waters. The units were also characterized by relatively high durability of the structure and resistance to enemy fire. Due to the use of tank turrets in their armament, they were called "river tanks". Cutters of this type took an active part in the operations of 1941-1945, being used on rivers such as the Volga, Pripyat, Bug and Odra.