Schaeffler Black Series radial insert bearings and housing unit. Black series radial insert ball bearings feature Durotect BS coatings matched to the specific application for wear protection, friction and corrosion protection. Black Series radial insert ball bearings are particularly easy to install, says Schaeffler Australia. Black Series housing units are engineered with flake graphite cast iron housing units, engineered in accordance with JIS B 1557, and feature a concave bore in which FAG radial insert ball bearings are fitted. Housing units are available as plummer block housing units, flanged housing units and take-up housing units to facilitate installation choice.