Garter springs are required for applications handling either low-viscosity fluids, shafts rotating at high RPM or high shaft eccentricity. As the figure below illustrates, the garter spring is made of a wire coiled helically, then joined at the ends. The figure below right shows how the two ends are joined; one end wound into a nib, then screwed into the opposite end. Because the garter spring produces maximum force with minimum deflection, it is very effective providing a constant radial tension between the primary lip and the shaft. This tension, combined with that of the lip’s elastomeric force, enables the seal to conform to the eccentricities of shaft rotation.