The RIDGID C-27HD (37638) 5/8 in. x 75 ft. Heavy Duty Inner Core Cable is ideal for cleaning 3" to 6" drain lines, including vents, laterals, and floor drains. The heavy duty inner core cable has a larger wire diameter than standard inner core cable, resulting in a stiffer cable. Its inner core resists kinking and provides good flexibility for negotiating tough bends and traps. The cable is suitable for use with K-6200, K-750, K-7500, and K-750R Drum Machines.