Abstract: A probe used for inspecting tubes or pipes comprises an elongated flexible shaft, a plurality of axially spaced guides on the shaft, the guides being engageable with the inner surface of a tube for maintaining the shaft substantially concentrically disposed within the tube, and a housing for a sensing element, the housing being secured to the shaft for rotation therewith and disposed between a pair of the guides, the housing having a tube contact area for engagement with the inner surface of the tube. The sum of the radial displacement of the contact area from the axis of the shaft of each of the housing and guides is greater than the inner diameter of the tube so as to cause the shaft to urge the housing and the pair of guides in radially opposed directions.