For 1 3/4" to 2 3/4" (44. 5 - 66. 9mm) Cylinders. Precision built for small cylinders. Stones are 3 1/2" long, assuring unusual accuracy. Stones cover full range, are easily changed, and available in four grits. Comes complete with 16410, 16420 and 16430 medium grit stone sets in sturdy storage case.