The accusharp® 5-stone precision sharpening kit allows you to manually sharpen your knives at a consistent angle. This kit provides precision sharpening designed to maintain accurate results for your knife's specific edge. The accusharp® precision sharpening kit is equipped with six angle and five stone options to keep your knife's edge razor sharp. Knife Clamp has settings for 11, 15, 18, 21, 25 and 30 degree angles..