Abstract: An extension unit is used in conjunction with wrench-type hand tools, such as socket and ratchet wrenches. One form of the unit includes a handle and an extension arm that has a plurality of spring-loaded balls thereon at distances that are spaced apart from each other along the longitudinal axis of the extension arm by increments that are uniform. A further extension element is attached to the handle and a bayonet coupling is used to properly align the further extension element with respect to the handle. A second form of the unit includes a spring loaded catch and spring loaded anchors.