Bearings are what allow the gears to rotate easily. They are generally produced from bronze or brass, and they healthy into races (or grooves) in the gearbox housing. Synchro rings have tooth on them that mesh Using the tooth over the gears, they usually also have friction products on them https://filter-gearbox24567.csublogs.com/41110813/5-easy-facts-about-filter-gearbox-described