Abstract: A washer for tightening and loosening threaded connectors includes an outer body having a radially inner opening larger than a diameter of a bolt and a radially outer surface adapted to absorb a reaction force of the bolt; and optionally a radially inner segment, and a spacer locatable between the radially inner segment and the nut, so that when only the radially outer body is interposed between the nut and the object for regular applications the washer functions as a reaction washer, when the radially outer body and the radially inner segment are interposed together between the nut and the object for applications when even and accurate bolt elongation is necessary the washer functions as a tension washer, and when the radially outer body, the radially inner segment, and the spacer are interposed between the nut and the object for applications when a precise bolt elongation is needed and a bolt elongation must be controlled the washer functions as a high precision washer.