DMT A-PROKIT Aligner Prokit Diamond Sharpener Made in: USA Category name: sharpeners Made in USA or imported New easy to store and carry container holds all the Aligner components 3 diamond stones in Extra-Fine, Fine, and Coarse plus a fine serrated sharpener accessory Sharpen knives faster than conventional stones with DMT's monocrystalline diamond surfaces No oil needed - sharpen dry or with water Durable construction will provide years of consistent performance and reliable service.