By using controlled pressure it is possible to use just one stone grit for polishing and honing. Stones are square end to hone to the end of step-cut end blind-end cylinders. 3 stones, 1\" long , 320 grit; Adjustable range 1 1/2\" to 3 1/8\" (38.1mm to 79.3mm); Note: See 530772 for replacement stones