Side faces of BST type bearings are flush-ground to provide the same face height difference for both the front and back faces. As a result, bearings of the same part number can be freely combined into DB, DBT, and DTBT configurations. Every single bearing is machined to the same face height so that when any arrangement is installed on a ball screw the unit has optimal preload. For this reason, no time-consuming preload adjustment is necessary.
NTN is one of the three largest bearing companies in the world with more than ninety years of manufacturing expertise in ball bearings.