The Sd.Kfz.251 mounted 6 crates, normally carried five 28 cm HE projectiles and one 32 cm napalm. The crate could tile from +5 degree to +45 degree. For left - and right - direction, the vehicle had to be moved. Crews were reduced to 7 after rocket equipment was mounted. The crew was outside the vehicle to clear from flame when rockets were launched, using control box to switch on the launch. It would take 10 seconds to launch 6 rockets. The range of HE projectiles was 1900 m, whereas that of napalm was 2200 m.

This weapon made its debut in 1942 on East Fronts. At first only saw services in the 3rd platoon of Engineering Company, Panzergrenadier. Later it was deployed to Army or Army Corps Rocket Companies. It soon nicknamed as "Walking Stuka" (Stuka Zu Fuss) due to its unique roars. It was a cheap yet successful weapon, with wide and effective cover range.