This tank wagon consisted of a tanker mounted on a four-wheel chassis. The tanker had a flip-top dome casing on top, along with strengthening bracing in two places around the tanker, mounted on an underframe.
It was white with the the red letters UD, for United Diaries creamery, milk bottling and distribution company, stencilled on the side. The chassis was bronze coloured.
The early production larger tank had the letters U and D outside of the bracing. The later, smaller tank had the letters UD in between the bracing.
Additional detail included a moulded hand brake on the chassis.