The Spyder 622TH Triple Deck Screen is a track-mounted aggregate screening plant featuring a 6′-0″ x 22′-0″ (1.83m x 6.7m) horizontal shaker screen. ... The Spyder 514TS3 is a patented, track-mounted, triple deck reverse screening plant designed for primary or secondary screening of rock, sand and gravel, soils and other materials. ...