Abstract: A packer element assembly includes an annular sealing element having inner and outer sides, wherein the sealing element is axially compressible from a first position to a set position, and first and second backup rings located on opposite ends of the sealing element. When the sealing element is axially compressed to the set position, the sealing element expands radially, and the backup rings rotate relative to the sealing element. A setting method may include locating the packer element assembly within a well casing bore, and axially compressing the packer element assembly to the set position. The sealing element expands radially such that the outer side of the sealing element expands against the well casing bore and the backup rings are rotated relative to the sealing element to eliminate a gap between a mandrel and the sealing element, thereby preventing extrusion of the sealing element along both inner and outer sides.