The CMT 791.015.00 is a 1 1/4 x 1/2-Inch Bearing. Be sure to keep the black shield right side up to correspond with the bearing rotation during reassembly. Features: * A replacement bearing for CMT Router Bits * Inside diameter: 1/2-Inch * Outside diameter: 1-1/4-Inch (31.7 mm) What"s In the Box: * CMT 791.015.00 1 1/4 x 1/2-Inch Bearing