11 (Sonderkraftfahrzeug – special motor vehicle) was a German half-track that saw widespread use in World War II.

The basic engineering for all the German half-tracks was developed during the Weimar era by the Reichswehr's Military Automotive Department, but final design and testing was farmed out to commercial firms with the understanding that production would be shared with multiple companies.

Borgward[Notes 1] was chosen to develop the second smallest of the German half-tracks and built a series of prototypes between 1934 and 1937.

Power was provided by a front-mounted Maybach six-cylinder, water-cooled, 4.17 litres (254 cu in) HL 42 TRKM gasoline engine of 100 horsepower (100 PS).

Maximum speed was 52.5 km/h (32.6 mph) and it could ford water .5 metres (1.6 ft) deep.

The rear suspension consisted of six double roadwheels, overlapping and interleaved in the Schachtellaufwerk system, mounted on swing arms sprung by torsion bars.

An idler wheel, mounted at the rear of the vehicle, was used to control track tension.

It had a six-cylinder, 3.485 litres (212.7 cu in), 71 horsepower (72 PS) Hansa-Lloyd Type 3500 L engine mounted in the front, a four-speed Hansa-Lloyd-Goliath transmission, had only four roadwheels per side and weighed 5 tonnes (4.9 long tons; 5.5 short tons).

[5] The first production model was the HL.kl.5 which still used the Type 3500 L engine and the Hansa-Lloyd-Goliath transmission, but was lengthened by two roadwheels per side.

11 chassis, but later Adlerwerke of Frankfurt-am-Main, Horch of Zwickau and Škoda of Mladá Boleslav were added to the production plan.

The ammunition compartment had racks to hold the shells and their propellant with side-opening doors.

[9] The later version created in 1944 was an anti aircraft vehicle using the armoured front superstructure of the Sd.Kfz.

[9] According to a reliable report the medium vehicle carries 760 kilograms (1,680 pounds) of bleach; a strip 1.7 meters (5 feet 7 inches) wide and 1.4 kilometers (just over a mile) long can be decontaminated by using a density of 300 grams (0.66 pounds) of bleach per square meter.

11/3 was equipped with a 500 litres (130 US gal) tank and spray system to lay down poison gas barriers.

The spray nozzle swung back and forth to cover a width of 16 metres (52 ft).

Unlike earlier Nebelwerfer ammunition vehicles it was given a wooden upper body with two compartments.

The forward cargo compartment was open-topped and lacked the racks of earlier models.