The carriages of the howitzers were modified for motor traction by mounting a hitch on each gun so they could be joined together nose to tail for transport. Each battery numbered four guns and their artillery tractor. Each gun had a caisson but instead of hooking the caissons to the guns as they would be for horse traction they were joined together from nose to tail and towed by their tractor. A drawback of the du Bocage system was its convoy weighed 26 tons which meant it was restricted to good quality roads, in good weather, with bridges capable of supporting its weight. The 4-ton 12 hp tractors could tow the convoy at over good roads in good weather dropping to in bad weather. If the convoy needed to cross gradients steeper than +12° or there was soft ground the tractor could unhook from its carriages and it could move forward alone. The tractor could then be anchored and use a powerful winch to drag its carriages forward.
