OREGON 28588A 12-Volt Electric Sure Sharp Saw Chain Includes 1 chain grinder, 3 sizes of sharpening stones (5/32-inch, 3/16-inch, 7/32-inch), and 1 collet wrench Can use an automobile poer adapter Sharpens any round-groud 90,91,1/4-inch,325-inch,3/8-inch or .404-inch-pitch chain New shank lock feature allows for easier stone replacement