These units come in forward plate and reversible plate compactors. The forward plate compactors can be used on asphalt or soil with most of the sizes. They have engine options from 4hp to 9hp depending on the size of compactor/tamp you need. You can use these for compaction of soil in trenches, on asphalt, curb & gutter work or large jobs with backfill. The reversible plate compactors/tamps range in size from the RP522 with a 4hp Honda to RP2250 with a 15hp Farymann engine. These units are ideal for compacting sand, gravel and mixed soil. They are available with a 16 wide plate to 32 wide plate for the larger compactors. Model RP790G reversible plate compactor shown