10 DIFFERENT SHARPENING KNIFE STONE : 10 pieces grinding stones with anti slip base,made of durable diamond material. They respectively are #150 #240 #320 #400 #600 #800 #1000 #1200 #1500 #3000 DIAMOND MATERIAL: The diamond sharpening knife stone is made from diamond, which turns out to be tougher, stronger and more durable than those made out of stone material. EASY TO USE: One of the most outstanding features of this diamond sharpening knife stone is that there is no need to use water when you are sharpening the knife. WIDELY USED: This type of sharpening knife stone can not only be used alone but more importantly, you can use it together with the knife sharpener. In this way, it can make the effect of sharpening a knife more precise and efficient. AFTER SALES GUARANTEE: If you have any questions about the use of the product, please contact us and we will try our best to solve the problem for you as soon as possible 10 Pcs Diamond Sharpening Stone,150/240/320/400/600/800/1000/1200/1500/3000 Diamond Sharpening Stone with Non-Slip Base for Kitchen knife & Outdoor knife