Abstract: The invention is an improved anchor for machine bolts and other similar fastening devices in masonry or other materials. The improved anchor consists primarily of a two-piece body structure. When in use the two-piece body structure is arranged for receiving a fastening device, such as a machine bolt or other similar fastener. The two-piece body structure is cylindrical on the exterior thereof with the offset between the first and second of the two pieces of the body structure being a cut or separation through the body structure at an angle to the longitudinal centerline of the two-piece body structure. Each of the two pieces of the two-piece body structure has a plurality of saw tooth-like cuts or serrations on a portion of the exterior surface. The saw tooth-like cuts on the first piece of the two-piece body structure being located 180.degree. from the saw tooth-like cuts on the second piece.