Turkish 404-tons Danube river monitors being built in England according to the magazine Mitteilungen aus dem Gebiete des Seewesens 1875 no. 11

Two monitors to serve on the Danube were being built in England. The armament consisted of 2 guns. Horsepower 100 nhp. Dimensions 125 x 28.5 x 10 (fore)-12 (aft) feet and a tonnage of 404 tons. None masts