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Floating bridges use floats or shallow-draft boats to support the crossing of land vehicles across large bodies of water. These armored vehicles can range from the size of Humvees to main battle tanks. Still, the amount of weight the bridge can accommodate at a time depends on the buoyancy of its supports.
One great example of a floating bridge is the M3 Amphibious Rig. The M3 is a self-propelled floating bridge mainly used for tanks and larger vehicles. M3s are also self-deployed using roads and can be connected to multiple rigs with ramps.
According to General Dynamics European Land Systems, the M3 is the most modern and fastest-to-deploy amphibious bridge and ferry system in terms of loading capacity, assembly, and in-water maneuverability.