Abstract: A swab cup for oil wells is provided which comprises means by which the elastic side walls of the cups can be radially expanded almost throughout their entire length. The oil well swab cup has a substantially cylindrical uniform wall thickness resilient annular body having a multiplicity of parallel metallic longitudinal wires imbedded in its external periphery, the lower end of each wire terminating in a hook-like formation extending into relatively free articulation with a retainer wire ring imbedded in the lower end of the body.