Abstract: Apparatus for tightening or loosening fasteners pneumatically, electrically, hydraulically and manually driven are disclosed, and in one example includes: a receiving member, rotatably supported in the apparatus for tightening or loosening, for receiving the fastener; a device for effecting rotation of the receiving member to tighten or loosen the fastener; and an apparatus which transfers a reaction force during tightening or loosening of the fasteners. The apparatus which transfers a reaction force includes: a first force-transmitting element rotatably attachable about a turning force axis of the device for effecting rotation; and a second force-transmitting element either rotatably attachable about, extensibly and retractably attachable along, or rotatably attachable about and extensibly and retractably attachable along at least a portion of the first element.