Caterpillar's U.S. Tier 4 Final, E.U. Stage IIIB, and Stage IV engines range from 4.1 kW (5.5 hp) to more than 895 kW (1200 hp), and meet industry expectations for reliability, performance, fuel and fluid efficiency, and component life, with significantly reduced emissions. Caterpillar has selected from a portfolio of engine and aftertreatment technologies to meet the latest emissions standards. The technology offering includes a diesel oxidation catalyst (DOC), diesel particular filter (DPF), and selective catalytic reduction (SCR.) Additionally, a “No DPF” aftertreatment package is available on select platforms. Cat's Clean Emissions Module is a rugged, modular aftertreatment platform that houses the Cat Regeneration System, a DOC, DPF, and the new SCR system. Its turbocharging solutions are based on engine size and application for increased productivity and fuel efficiency. Its fuel injection system was designed for carefully timed microbursts for clean and most efficient fuel burn.