Abstract: A drive unit for gripping and rotating a fuel rod during inspection of the fuel rod. A housing has a drive motor mounted at its first end with a spindle rotatably mounted in the housing and directly coupled to the drive motor. A recess at one end of the spindle adjacent the second end of the housing receives a substantially donut shaped rubber bladder. A flanged port that extends radially from the bladder and is in fluid communication with the interior of the bladder provides a means for pressurizing the bladder. This causes radial inward expansion of the bladder for gripping a fuel rod to be inspected.