The model is approximately 1:12 scale and I have tried to replicate all of the features of the original vehicle.
It has six-wheel drive with four differentials (one inter axle differential between the tandem rear wheels).
The gearbox (a modified version of one of Philip Webb's ( I think) is four speed, neutral and reverse coupled to a two speed and neutral transfer box.
The front and rear winches are driven by chain from the winch drive box, and have a forward/reverse and neutral drive box (1:1 ratio). Each rear boom cable winch is independently selectable and the booms are as per original- hand winched to raise or lower each hand winch features a ratchet locking mechanism.
Steering is via a bevel reduction box and drag link.
The rear body has opening lidded storage boxes. I have made extensive use of narrow strips and girders and a multitude of modern parts. The main colour is French yellow.