SD2:M21 MMC

 is a United States Artillery unit in Steel Division II.

Background
Combining the M1 81mm mortar and the reliable M3 half-track, the M21 was produced by the White Motor Company and introduced in 1944. It served for less than a year in the terminal stages of the war, before being pulled out of production after the mortar was deemed outclassed. Only 110 were produced.

Each Armored Infantry Battalion and Armored Battalion has a Mortar Platoon of three M21 in the Headquarters Company.