Double Direction Angular Contact Thrust Ball Bearings is a kind of high accuracy bearing that specially designed for used in the main shaft of machine tools, it can bear axial load in two directions.In comparison to the series 511 thrust ball bearing, Assemble in this kind of bearing has small steel ball diameter and more quantities, besides,it has a 60°contact angle,thus this bearings' centrifugal force influence is small and is more suitable for applying to high speed rotating and big rigidity.