Mortars are mainly medium calibre weapons. However, mortars both bigger and smaller than this have been made. An example of a smaller mortar is the British 51 mm Light Mortar. The 51 mm is carried by just one soldier. It is made up of only a tube and a base plate. A bigger example is the Soviet 2S4 M1975 "Tyulpan" (tulip flower) 240 mm self-propelled mortar.