Use this 400 grit sharpening stone for achieving a fine edge on your blade. Unmounted whetstones stones must be mounted to a stone blank (sold separately) to be used with the Edge Pro sharpening systems. Pro sharpeners and home enthusiasts who go through many knife sharpener stones can remove their worn out stones from the existing stone blank and mount these unmounted stones themselves for a considerable savings. EdgePro suggests mounting the stones using 3M's Super 77 adhesive spray.
Please note that unmounted stones are very thin and so very fragile. We wrap them carefully in bubble wrap so they'll make it to you in one piece, but you must exercise extreme care when unwrapping and mounting them. We are not responsible for broken or cracked stones after they reach you.