The Soviet AT-1 SPG:

• In 1932 the problem of moving 76mm regimental guns was solved by using the chassis of the T-26 with an enclosed cabin. The real role of this vehicle was to provide infantry support rather than fulfill an artillery role, like the SU-1.

• Mounting a 76mm PS-3 cannon and 2x DP machineguns it had formidable firepower but due to the Soviets fascination with tankettes it had very thin armor. The spacious interior sported 46 rounds and could open up its sides to give more room to crews for reloading.

• The AT-1 could achieve a speed of 30km/h, with its 90hp engine and weight of 9.6t. It has an overall armor of 13mm which would make it resistant to small arms.

• Only 10 were built.