The NPI Helical spring is made from flat ribbon stainless steel and other alloys wound into a round cross section helix geometry. The H Series is for use in U-Cup seals and other components as a radial or axial compression energizer and produces a very high unit load over a small deflection range. Normally used in static or slow dynamic applications and often when very low temperatures are present, the H Spring is available in five standard sizes and can be ordered by the foot or cut and welded to specific diameters. Custom sizes and materials are also available. Cross sections as small as .015" and diameters less than .100" can be made. NPI can provide load estimates for new designs that require specific loads. Contact NPI for details.