Some information about the prototype:
The 2S1 Gvozdika (Russian: 2С1 "Гвоздика"; Wersja: Carnation) is a Soviet 122-mm self-propelled howitzer that resembles the PT-76 but is essentially a version of the MT-LB APC, mounting the howitzer 2A.18. "2S1" is its GRAU designation. .">Alternative Russian designation is SAU-122 but in the Russian Army it is commonly known as Gvozdika ( "Carnation"). The 2S1 is fully amphibious with very little preparation, and once afloat is propelled by its tracks. A wider variety of tracks are also available that allow the 2S1 to operate in snow or swamp conditions. It is NBC's protected and has infra-red night-vision capability.
The overall box image:
