A dual seal packer is shown having a central mandrel which carries upper and lower seal assemblies which straddle an outer cage assembly. Rocker type slips are carried in the cage assembly and are set by a single expander ring. Special support surfaces on the slips cooperate with mating support surfaces on the cage assembly to provide support for the slips under tensive and compressive loading. The slips and upper and lower seal assemblies are set in a single step operation by rotating the mandrel to the right while holding tension on the well string from the surface.