Double Row Self-aligning Bearings utilize an inner ring with two rows of balls in two deep raceways, and an outer ring with a single spherical raceway. In this way, the inner and outer rings can be misaligned relative to each other. The resulting effect is a comparatively large angle imposing moment loads upon the balls. The boundary dimensions of the 1200 and 1300 series are the same as the 6200 and 6300 single row deep groove bearings. NTN Self-Aligning Ball Bearing, Cylindrical Bore, Series: 12 Series, 17 mm Bore Dia, 40 mm Outside Dia, 2 Rows, 12 mm W, Open Closure, 8000 N, High Carbon Chrome Steel Bearing, Nylon Cage, 16000 RPM Grease/20000 RPM Oil Maximum, -40 to 120 °C