... 1) Spherical roller bearings are principally provided with two rows of symmetrical spherical rollers and a common sphere ... , this type of bearings permits a low limiting speed.2.Bearing Number(1): 21308, 21308K, 21308KW33C3, 21308W33C3, ... 21317W33C3, 21318, 21318K, 21318KW33C3, 21318W33C3, 21319, 21319K Bearing Number(2): 22205, 22205K, 22205KW33C3, 22205W33C3, 22206, 22206K, 22206KW33C3, 22206W33C3 ...