Oslyabya showed the cost of a second-class battleship

Oslyabya carried 10-inch rather than 12-inch main guns, eleven 6-inch guns, numerous smaller weapons, torpedo tubes, and mines. Her turrets received Krupp cemented armor while the much larger waterline target retained a Harvey-armored belt. The other two Peresvet-class ships had already been sunk at Port Arthur, where shallow water allowed Japan to refloat and reuse them. One was later sold back to Russia and lost to a mine off Port Said in 1917. The class history gives concrete consequences to the uneven protection scheme rather than treating armor quality as an abstract specification.