Dual amplitude settings, standard on Caterpillar's 500E Series of soil compactors, expand the range of applications by permitting the operator to adapt compaction effort to changes in lift thickness, soil characteristics and density requirements. The 500E Series has four models, with weights ranging from 11.1 to 15.7 metric tons. Buyers can choose a machine suitably matched to frequent needs, from 12-inch lifts not exceeding 95 percent standard Proctor, to 18-inch lifts exceeding 98 percent standard Proctor. Compactors feature a dual-pump drive system that independently powers the rear axle and drum for positive tractive effort. Estimated list prices: $135,000 to $180,000.