Nikro 860472 - 33ft Replacement Inner Rod for Orange and Black Jacketed Air Duct Cleaning System 33’ Replacement Inner Rod for Orange Jacketed Air Duct Cleaning System Inject lithium grease into hose on both ends and on replacement rod before assembly. Allen nuts are concave with a notch in them so this requires that you gently tighten on nut and then move to the next. Toggle back and forth between the nuts applying more torque each time until you can not tighten any more. Rules for use: Do not turn faster than 320 rpm Do not used coiled up with more than 360 degrees in total turns. Only use with a clutched drill.