TT Technology GRUNDOWINCH® RW5000 CONSTANT TENSION VARIABLE SPEED WINCH with only 33 hours, This Constant Tension Variable Speed Winch is part of the rugged Grundowinch line of hydrostatic constant-tension winches specially designed for the variable conditions in below-grade work. Features protective cable storage with diesel engine; as well as an adjustable boom system. Portable and powerful, Grundowinch is well-suited for underground utility construction applications including: