Template:LA-AMTBHistory

Four Anti Motor Torpedo Boat (AMTB) batteries were built for the Harbor Defense of Los Angeles during World War II under Job No. FS-8 at a total cost of $76,576.03. Each of the four batteries consisted of two fixed gun emplacements of 90mm M1 guns on M3 pedestal mounts with a heavy shield. Additionally provisions were made for two temporary mobile gun positions at each of the four locations. Two of the AMTB batteries were located on Fort MacArthur and the other two were located off the main reservation at Terminal Island and Bluff Park, Long Beach.

The mission of these AMTB batteries was both to defend against smaller faster naval vessels that might evade the larger batteries and to defend against aerial attack.