SdKfz 138 Marder III Ausf. M
The last Marder III variant was based on the Panzer 38(t) Ausf. M (with Ausf. M standing for Mittelmotor (middle engine)), again armed with the PaK40 75 mm anti-tank gun. In this variant, the gun and fighting compartment were located at the rear. Unlike in the previous two Marder IIIs, this compartment was closed at the rear, though still open-topped. It could only carry 27 rounds of ammunition. The Ausf. M did not carry a machinegun in its hull, instead a MG 34 or MG 42 was carried by the crew.
The Ausf. M was the variant which was produced in the largest numbers, some 975 vehicles being manufactured in 1943 and early 1944. Its full name was the SdKfz138, Panzerjäger 38(t) mit 7.5cm PaK40/3 Ausf. M.