QA1's EMB Nylon Race Series spherical bearings feature an injection molded race for superior ball to race conformity. This race results in the bearing being completely self-sealing and self-lubricating, keeping dirt and debris out. EMB Series spherical bearings are ideal for low load, low oscillation applications. BALL, 52100 Bearing Steel, Heat Treated, Hard Chrome Plated, Precision Ground, , RACE, Nylon/PTFE, Self-Lubricating, Self-Sealing, 0.006" - 0.008" Deep 60_ V-Groove - 56 TPI.