Originally a light tank design, the M7 grew until a redesignation to medium was necessary. The M7 used the same 75mm gun as the M4 Sherman, but its trailing idler suspension superficially resembled that of the M3 or M5 light tanks. A stowage box is mounted behind the turret on this example. (Picture courtesy Armor Foto.)
The cast hull armor of the M7 was well rounded. (Picture from Development of Armored Vehicles, volume 1: Tanks.)
Details of the vertical volute spring suspension are visible in this closer shot. The drivers' vision slots are visible in front of their hatches, and the TC's and loader's split hatches are open on the turret roof. The aperture for the gunner's M5A1 telescopic sight is on the gun shield's left side, and the coaxial machine gun was placed on the right side of the main weapon.