For use on the following chain types:
.325" (Oregon 20, 21, 22 & 95 chains only); 3/8" (all except Oregon #90 & 91 chains); .404". Wheel is designed to work with all of the Oregon Mini Grinders.
•OD: 4-1/8"
•Center Hole Diameter: 7/8"
•Thickness: 3/16" (4.8mm)