In the early 1930s, the French Army would issue a requirement for a new armoured vehicle able to carry supplies to the infantry while under fire. It would also have to carry the new 81mm Brandt Mle 27 mortar. This was issued to three French firms: Renault, Citroën and Brandt. Brandt decided to import some Carden-Loyd Mark VI from Vickers and propose it to the commission. Instead, the three firms were invited to loosely copy the British design to avoid buying a license.

Given that the Carden-Loyd Mark VI was equipped with a towable trailer, it should be no surprise that the selected Renault UE Chenillette had its own trailer, the Renault UK. Renault largely copied the suspension system from Carden-Loyd and even patented it. This solved issues with tracks being thrown at high speeds that Renault's original designs had suffered from.

In addition to the 350kg capacity of the tractor basket (less than the 500kg required) the towed trailer could carry around 600kg, more than the 400kg required. The trailer could be easily unhitched from the inside of the vehicle, meaning the crew did not have to leave the vehicle while under fire. An antitank gun could also be towed at the rear of the trailer.

Our UK trailer was made by Kraetzer, who also made the original UE.