Delrin triangular bearing reduces sticking, scratching and improves stability. The 3 in 1 flush trim bits with Delrin Triangular bearings solves 3 of the most common problems that occur in flush trimming in cabinet shops:. The freezing of the bearings from glue; the Delrin with it's anti-stick properties greatly reduces the likelihood of bearing failure. The extended guide surface of the new Delrin bearing will perfectly match the work surface without scratching and guarantees the maximum router stability. The shear angle cutting edge reduces the need for filing. Cut Diameter: 3/4". Cut Length / Outside Diameter: 5/8". Shank Diameter: 1/4".