Trim a sink cutout flush with the bowl in stages using these "over-hang" and flush trim bits in tandem. The overhang bits are equipped with non-marring ultra-glide bearings that are tapered to match the slope of the bowl's side. A first pass with the appropriate overhang bit cleans the cutout edge, leaving a very slight overhang at the underside of the counter. A pass with the flush-trim bit completes the operation, #57154, diameter (D): 3/4, cutting Height (B): 1, shank (d): 1/2, overall length (L): 3-1/2, type: flush trim, replacement bearing: 47709, flutes: 2, 57154 carbide Tipped sink and trim with ultra-glide ball bearing guide solid surface 3/4 dia x 1 inch x 1/2 shank