2TBy Construction Is The Same As 2S, Except Rubber Lip Is Tripled. Therefore, It Seals Better But Has Even Larger Friction. The Permitted Speeds Are Much Lower, Up To 500. It Emerges Out Of External Ring Width And Is Applied Only With Special Bearings For The Agricultural Machines (Practically Standard Sealing For The Disc Harrow Bearings) And To The Less Extent, Y-Bearing Program
