... on the shirttail increases gauge holding capability and bearing life. 3.Bearing StructureHigh precision bearing with two thrust faces. Balls lock the ... ensure good contact being kept on two sealing surfaces of metal rings by elastic force, and achieve the bearing seal. In ... 3 7/8, 3 5/8,4 1/2,4 5/8,5 1/2,6 ,6 1/2,6 3/4,7 7/8,8 1/2,8 3/4,9 1/2,9 5/8,9 7/8,10 5/8,12 1/4,13 3/4,14 3/4,14 5/8,16,17 1/2 ...