ATRO Engineered Systems, Inc.’s Shackle Kits and Spring Pins provide a long-life, no maintenance/no grease solution to labor intensive bi-metal bushings and pins. The design limits lateral movement of the pin while still allowing proper articulation of the pin within the bushing. This provides side stability and keeps the load and stress centered on the spring assembly thereby improving spring pin performance and longevity, ride quantity and extending the life of the spring and connecting hardware. The polyurethane material is impervious to environmental elements and has a self-lubricating quality that eliminates costly and ineffective maintenance procedures. ATRO uses the same sidebars as Original Equipment pins/bushings and they are protected by a clear zinc coating to resist corrosion. ATRO’s Shackle Kits and Spring Pins are backed by a three year warranty.