Superior Electric SE 6203-2RS Replacement Ball Bearing - 17 x 40 x 12 (mm) Replaces Makita 211256-2, Bosch 2610024748, Delta 1086894S Side 1: Seal | Side 2: Seal | Inner Diameter: 17 mm Outer Diameter: 40 mm | Width: 12 mm Axial Load: 0.9 KN | RPM:  4000 Tolerance: ABEC-3 Class 3 | Material: E51100, 100Cr6 Bearing Life: 3 Years, varies on application