Developed and fielded in 1917, The Mark I Gun Carrier was an Armored vehicle, designed to transport cannon and ammunition to forward positions - without concern for transitioning over trenches or other obstacles. Weighing 6 tons, they crewed 4 men. The Carrier was designed to transport either a single 60-Pound Gun barrel or several 6-inch Howitzers (via Tow). The Mark I Carrier traditionally did not carry defensive/offensive weaponry. They could (and often did), Mount and deploy the 60-Pound Gun (which could be quickly installed, turning The Mark I into a "makeshift "weapons platform".
The Carrier could carry an additional 130 rounds of different type shells. Later, it was used to transport as many as 24 soldiers at a time (as an early version of an Armored Personnel Carrier). The track system, although linked and not independently operated as with much later Tanks and related Armor Vehicles). Still, The Mark I could transition over a 6-foot Trench with relative ease. Only 48 were built, with production ending with The War.