Due to the high trajectory, high rate of fire, and their light weight, mortars are especially suited to terrain with natural cover, in built-up areas and in circumstances with great altitude differences. Due to the major-general Vilho Nenonen's intitiative Finland has built mortars since the early 1930s, and although they haven't been exported, the designs have been used in many countries. The largest technological transfer of the Finnish mortar technology did take place in the 1950s, when the technology was transferred to Israel for Soltam.