2-Stone Hone Fits Cylinders 11/16" to 2 1/2" (17.4 - 63.5mm). Controlled pressure makes it possible to polish or hone with just one stone grit. Square ends of stones hone to the end in step-cut and blind-end cylinders. 240 grit stones are 1 1/8" long. Flexible driver.
(California Prop 65)