Angular contact ball bearings are non-separable bearings which have a certain contact angle in the radial direction relative to the straight line that runs through the point where each ball makes contact with the inner and outer rings. In addition to radial loads, single direction axial loads can also be accommodated by angular contact ball bearings. Furthermore, since an axial load is generated from a radial force, these bearings are generally used in pairs facing each other. Standard type, high speed use type and ultra high speed varieties of angular contact ball bearings are available through NTN, and there are also many duplex varieties. A bearing accuracy of JIS Class 5 or higher is applied to duplex type angular contact ball bearings, and in many cases they are given a preload, in compliance with standard preload levels, before being used in an application. NTN Angular Contact Ball Bearing, Round Bore, Series: 72 Series, 17 mm Bore Dia, 40 mm Outside Dia, 1 Row, 12 mm W, 30 °Contact, Open Closure, 12000 N, High Carbon Chrome Steel Bearing, Steel Cage, 19000 RPM Grease/26000 RPM Oil Maximum, -40 to 120 °C