SD2:M4 HST

 is a United States Support unit in Steel Division II.

Background
M4 High Speed tractor was designed off the M2 Light tank. These were designed be a prime mover for American Heavy Artillery like M1A1 155mm Long Tom. These vehicles can carry 11 artillerymen along with equipment for the gun.

Strategy
M4 HST are the only transportation options for the M1A1 155mm Long Tom.