Screening Flexibility with Ultimate Maneuverability. Create three fractions from a single material stream with the Backers three fraction MTA (tracked and wheeled) star screen. By initially passing all material over the course deck, even wet or sticky organics are loosened increasing the overall screening efficiency and producing a more consistent medium and fines product. Add the optional Grizzly, and a fourth very course fraction can be produced; or attach an optional Wind Sifter to remove contaminants from both screening decks. For ultimate flexibility and throughput Backers three-fraction star screens are unparalleled.