These are the hardworking elements of the Gator Navy that work silently in the background. They consist of commercial container ships that have been converted to supply the logistical needs of the USMC at war. This type of ship is also a defence against the possibility of a devastating first strike on land assets. They supply nearly everything "...from tanks and ammunition to food and water and from fuel to spare parts and engine oil." The MPF is part of the US Military Sealift Command. What makes them special is the ability to launch amphibious craft and vehicles using a submerged stern ramp. A Maritime Prepositioning Force (Future) [MPF(F)] is already being planned, with more features.
Amphibious Warfare (N753) & click on link at the bottom right
Maritime Prepositioning Ships - T-AK
Maritime Prepositioning Force