... It is equipped with a lifting system,single drum drawworks, hydraulically raised double or single mast and famous engine and ALLISON ... operation and maintenance.Design features:1.68.90 ft ( 21m ) double section mast 59.06 ft ( 18m ) single section mast. 2 ... full drive chassis, fast movement, good cross-country capability. 3.Double drum drawworks, band brake, without auxiliary brake. 4.Mast base and ...