Single row angular contact ball bearings feature raceways with high and low shoulders. These opposing raceways are designed to carry thrust load in one direction. NTN can preload the bearings at the factory so that the correct load will develop once the bearing is put into service. The bearings in this series are assembled with a specific internal clearance, so that they will have a specified contact angle under load. The standard contact angle used by NTN is 30° but, in many cases, a 40° contact angle can also be specified. We also offer special high-speed bearings with phenolic resin cages with a 15° contact angle.Double row angular contact ball bearings have an inner and outer ring with a double raceway. The two rows are so related that the contact angle is similar to a pair of back-to-back single row bearings. NTN’s 5200 and 5300 series offer continuous races and can carry thrust loads in either direction. The 3200 and 3300 series have filling slots, so it is necessary to mount them with the thrust load acting against the un-notched face of the rings.