Abstract: An extension handle apparatus, for use with a conventional wrench having a handle and an opening defined within and adjacent a free end of the handle, the extension handle apparatus including a tubular sleeve member defining an open port at one end thereof and an open interior space for receiving the wrench handle. A plurality of aligned, square bolt-receiving openings are provided within two opposed walls of the tubular sleeve member, and locking means extend through predetermined and opposed ones of the bolt-receiving openings in the sleeve member and through the wrench handle opening for locking the sleeve member into safe and secure position on the wrench handle.