Among the early deliveries of British vehicles to Russia was a small quantity of Scammell Pioneer SV2S 6x4 Heavy Breakdown Tractors.
Build from 1939 on and equipped with a robust 102hp Gardner Diesel engine, a powerful 8-ton winch and a 3ton crane, the Pioneer SV2S soon proved its efficiency as a recovery vehicle.
A pair of tracks could be fitted over each set of the huge 13.50-20.00 rear wheels, effectively converting the vehicle into an half track.
An open crate-like locker under the drivers cab was designed to carry these tracks.
Due to the lack of heavy artillery tractors and recovery vehicles, the car should have been welcomed by the respective Red Army units.

Special thanks once again to Mr. Ferdinand Hejl, Czech Republic, for providing precious informations.