The 50 mm bomb thrower on the Valentine Mk II and Mk III is beside the main gun.
The 50 mm S-11 mortar on the Object 701.
A 50 mm mortar is the lightest type of mortar fielded. With the exception of the Type 89 Grenade Discharger thse are exclusive to vehicles in FHSW. 50 mm Mortars are present on two Soviet tanks and several British tanks. On the Soviet side the 50 mm S-11 mortar is exclusive to the two versions of the Object 701, prototypes of the IS-4. A 50 mm mortar or 2 inch bomb thrower as it was called is fitted on a number of British tanks and may launch either smoke bombs or high explosive, on some vehicles either type is available. These bomb throwers are on Crusader cruiser tanks, the Valentine infantry tank and the TOG-2 heavy tank. Mortars on crusader tanks only launch smoke bombs, while Valentine Mk II and III tanks can also fire high explosive (these have the suffix _rr in the game code). The mortar on the TOG-2 fires high explosive exclusively.