Patent ID: 7465881

Claim:
A coupler stem assembly, comprising: a) a coupler that includes: i) polymer material that has been molded to a predetermined shape; ii) an outer surface that is threaded and provided with a coupler axis; iii) an inner surface that defines a cavity and that includes a retaining member; and b) a stem that includes: i) an outer stem surface that is provided with a stem axis and that is shaped to fit within the cavity defined by the inner surface of the coupler; and ii) a retaining surface that is located on the outer stem surface and shaped to engage with the retaining member of the inner surface of the coupler, wherein the stem further comprises a groove and a guide surface that are located on the outer stem surface, the groove is dimensioned to accept the retaining member and the guide surface is configured to orient the coupler so that the retaining member contacts the retaining surface on the stem.