Abstract: An anchor to inhibit rotation of a device relative to an oil well casing, comprising a tubular mandrel adapted for direct or indirect connection to the device; a rotatable cylindrical housing with a plurality of apertures and able to receive at least a portion of the mandrel concentrically therethrough; a plurality of spaced apart anchoring slips disposed between the housing and the mandrel in registry with respective ones of the apertures in the housing's outer surface; a rotation mechanism associated with the mandrel to engage and then move respective ones of the anchoring slips radially towards and then into temporarily anchoring contact with the casing; and one or more drag blocks disposed in the housing in registry with respective ones of the apertures in the housing's outer surface to extend radially outwardly therefrom, each of the drag blocks being normally biased into frictional contact with the casing.