A towing vessel is a commercial vessel, designed for towing a mining plant, processing unit or the like. These ships are generally between 150 tons and 800 tons. They are not usually streamlined, because they usually do not need to enter atmosphere. Towing vessels are usually equipped with robot arms, automatic grapnels and a towing hook-up. They are usually equipped with a larger-than-usual computer, so that the ship computer can operate the maneuver and jump modules which are attached to the trailers.