M-3 75mm GMC (1941): This was fitted a M1897 gun (75mm Short Tank Gun), with a shield (DR 25), on a pedestal behind the cab. While the M-3 proved quite effective as a tank-destroyer against Japanese armor in 1942, it proved much less useful against German tanks in North Africa in 1942-43. Although some 2,200 were built, most were converted back to infantry carriers; less than 850 reached the field. Crew: 6, Ammo: 59x75mm
T48 57mm GMC (1942): The US M-1 57mm gun was a copy of the British 6-pdr AT gun (57mm Medium Tank Gun), so it was felt useful to fit the weapon to a halftrack. However, the US Army lost interest and by the time the British received the vehicle, the 6-pdr was no longer fully effective against German armor. The British ended up shipping most of the 1,000 T-48's built to Russia, where it was known as the SU-57. It came with a DR 25 gunshield. Crew: 5: Ammo: 99x57mm.
T-19 105mm HMC (1942): The M2A1 howitzer (105mm Short Howitzer) was fitted to a reinforced halftrack. Due to the mounting, it could only reach a maximum range of some 12,000 yards. Also, onboard ammo capacity was extremely limited, although a trailer could carry more. Some 342 were built, but only a small number actually saw service in North Africa. It retained a M-2HB with 300 rounds. Crew: 6: Ammo: 8x105mm
M-4 81mm MMC: This mounted a M-1 81mm mortar in the bed, along with a pintle-mounted M-1919A4.The mortar was intended to be fired dismounted; inside the vehicle, traverse was limited to a small rear arc. 572 built. Crew: 6. ammo: 96x81mm, 2,000x30-cal.
M-4A1 81mm MMC: Similar to the M-4, but the mortar was intended to be fired from the cargo bed and had full traverse. 600 built.
M-21 81mm MMC: Similar to the M-4, but the mortar faced forward, and secondary armament was a M-2HB with 400 rounds. 110 built.