It is a 'Kettenkrad', the NSU HK101 SdKfz 2 kleines Kettenkraftrad. That particular vehicle belongs to the Ramcke Brigade (Luftwaffe Fallschirmjäger -- parachute troops) in North Africa, probably Libya. It's a mid production model, identifiable by the reinforced front fork design, the front towing lugs having been moved from the upper hull front above the front track fenders to the lower front hull between the front fork and the sprocket drive wheels, and the lack of the reinforcing panels that would fill the space in the handrails on the rear.
The Kettenkrad was developed as a light artillery tractor to tow artillery pieces in moutainous terrain, its size constraint being that it had to fit into the cargo compartment of a Ju-52. It became useful for a variety of duties, including laying field telephone wire; these were formal variants, the SdKfz. 2/1 "kleines Kettenkraftrad fur Feldfernkabel" and SdKfz. 2/2 "kleines Kettenkraftrad fur schwere Feldfernkabel." Both vehicles were used in conjunction with a trailer and had field communication wire spools mounted behind the driver. The 2/1 vehicle mounted a small wire spool and frame similar to the backpack piece used by the infantry. The 2/2 utilized much larger spools, two of which were mounted on a frame behind the driver. Additional spools were mounted in a specialized trailer.
Normally steered with the handlebars (at small angles of turn they operated normally, at larger angles the mechanism automatically braked the inside track to decrease the turning radius), they were not actually necessary, and an emergency procedure for driving the vehicle without the front forks was taught.
The Kettenkrad had a bench seat for two people at the rear. Later in the war, an enlarged version with one additional road wheel per side and a second bench seat facing forward was developed, although it did not go into mass production.
The Kettenkrad suffered from a number of weaknesses; it had a high center of gravity, and turning around on a slope had to be done carefully. Also, its ability to drive up out of holes was limited; it was possible for a Kettenkrad to bury itself nose-down in a large enough hole so that it could neither go forward or back. Finally, in a production decision to save on the use of steel, the transmission of the Kettenkrad was largely made of aluminum, and suffered a high rate of failure (copies of the hardware made of proper steel do not suffer from the high failure rate, so the problem is one of materials limitation, not faults in the design).
More than 8,300 Kettenkrads were produced during WWII, and it remained in production after the war, with 550 being produced and sold to farmers as light tractors.
