 Stephens' hull design looked like a miniature version of that of the DUKW, and just like it, the 'Seep' was going to have a screw propeller, driven by a power take-off, operating in a dedicated tunnel faired into the rear end bodywork, as well as a proper rudder.The construction of the vehicle was developed in competition by Marmon-Herrington and Ford Motor Company.Marmon-Herrington specialized in all-wheel drive vehicles.