Torque link uses a coil spring to absorb engine torque and increase traction to rear tires. The dual shaft design allows engine torque and brake bushings to be adjusted separately. A single red (87 durometer) poly bushing is included. Other bushings are available for additional tuning options. Unit requires a 5" O.D. x 6-5/8" or 7" tall coil spring, sold separately. Unit is 18-1/2" long overall and most commonly used with two 3/4"-16 rods ends (1-RH Female and 1-LH Male) and a 3/4" suspension tube. Subtract 21-1/2" from center-to-center of the chassis mounting distance to determine required tube length. 8.5 lbs. without spring.