Spherical roller bearings are double-row, self-retaining units consisting of solid outer rings with a spherical raceway, solid inner rings, and barrel rollers with cages. The inner rings have cylindrical or tapered bores. The symmetrical barrel rollers align themselves freely on the spherical outer ring raceway. This compensates for shaft deflections and misalignment errors at the bearing seating locations. The different versions are designated by so-called suffix letters: A = modified inner construction, B = modified inner construction, E1 = reinforced version (standard), K = tapered bore 1:12, K30 = tapered bore 1:30, M = solid brass cage, TVPB = plastic cage. Special feature: solid brass cage, open design.