Best by Far - Yet Competitively Priced. Micrometer head assures accuracy in feeding. Expands quickly to cylinder size with fast action rack and pinion. Bottom guard plate helps prevent stones from accidentally hitting the crankshaft. Universal joint action makes grinding of back cylinder easy. Large Hone ----------------------------------------------------------------------------------------------------- Cylinder Rack Set 80 180 280 500 Special Size Range Part # Grit Grit Grit Grit Hard Weight Bond for Steel 150 Grit --------------------------------------------------------------------------------------------------- 2 3/4"- 15550 15680 15690 15700 ------------------ 3 3/4" 1lb *15740 69.8-95mm ---------------------------------------------------------------------------------------------------- 3"-4 1/4" 15540 15500 15510 15520 15990 15490 76.2- 108mm 1lb.2oz. ----------------------------------------------------------------------------------------------------- 4"-61/4" 15530 15500 15510 15520 15990 15490 100-158mm 1lb.6oz. ----------------------------------------------------------------------------------------------------- 6 1/8"-101/4" 15560 155-260mm 1lb.4oz. 15500 15510 15520 15990 15490 ------------------------------------------------------------------------------------------------------ *15910-Body (green) *15960.70- Pinion collar sub assy used to be 15270 head & shaft assy *15060- Yoke & Ring Assy- 5 1/8" *15130.70- Driver Extension *15130- approx 7" *15550- Low profile *15530- High Profile *8 PTS KEROSENE & 1 PT LGT OIL** *Screws are wh