The All Purpose Sharpening Stone "aiguise-tout" is an oval section stone that offers a very good grip. It can sharpen all kinds of knives: Sushi knife, chef's knife, kitchen knife, pocket knife, fruit knife and boning knife and all garden or wood tools (planer blade, wood chisel, etc.) Pyrenean whetstones can be used dry, but also wet (which is recommended) - in this case, the contact with the blade will be a bit softer. This stone does not require any particular maintenance. After a certain period of use & if necessary, you can clean the stone with washing-up liquid, brushing it under hot water.