The Global double sided wetstone includes both medium and coarse ceramic surfaces. The ceramic surface can be used to produce a very fine, sharp edge on any knife. (except serrated knives.) A medium grade ceramic wetstone suitable for sharpening all straight edged knives. Includes medium and coarse grade ceramic surfaces - to allow you to create a very fine edge on your knives. A very efficient method of sharpening knives. Like all knife sharpeners a wetstone should be used every time you use your knife - for best results. Gift Boxed Grit grades 240/1000 Instructions included. Supplied with plastic base to hold the whetstone steady whilst it is in use. Material: Ceramic & Plastic. Dimensions: 18cm x 5cm.