For the ultimate in performance spherical bearings, look no further than QA1's SLB Endura Loader Slot Series spherical bearings. SLB Series spherical bearings are completely self-sealing and self-lubricating because of their Nylon/PTFE injection molded race that keeps dirt and debris out. This design results in metal to metal support for heavy shock loads and smooth operation for low and moderate loads. The ball is made with 52100 bearing steel that has been heat treated, hard chrome plated and precision ground. There is a PTFE liner that is self-lubricating and self-sealing, with a race made with heat treated stainless steel. These bearings also have metal-to-metal support for heavy shock loads.