A buoy tender is a type of vessel used to maintain and replace navigational buoys. Project 419 (NATO reporting name: Sura class) is a mooring/buoy tender of the Russian Navy. The Sura class tenders are equipped with a 65-ton heavy lift gantry at the stern.

The ship has 87 m length overall, beam of 15 m, and displacement of 2260 tons at standard load and 3150 tons at full load. The ship has diesel-electric propulsion system. It includes a diesel engine connected to an electrical generator, creating electricity that powers electric motors, four 412 kW diesel generators, two 270 kW diesel generator and one 67 kW diesel generator. The ship is equipped with two 885 hp electric motors driving two fixed pitch propellers.

The vessel has a speed of 13.2 knots, a range of 4000 nmi at 10 knots and an endurance of 20 days. The vessels are also equipped with Don navigation radar.

Mooring/buoy tender KIL-25 laid down at the Neptun Werft Shipyard, Rostock, East Germany (yard No.149/1244), launched on 17 January 1969, commissioned on 30 August 1969 and was assigned to the Black Sea Fleet.

Now in service.