Hone and removes glaze form engine cylinders from 2" to 7" in diameter. Hone includes medium grit stones. Has a spread limiter and a adjustable spring for the tension Hone and remove glaze from engine cylinders from 2" to 7" (51 to 178mm) in diameter. Adjust spring tension for positive cutting action and set diameter with spread limiter. Hone includes medium 240 grit stones.