Universal Angled

You can test knives up to 2" wide

no tools required

There are a lot of very good stones of different thickness

Gritomatic Silicon Carbide 2500 Silicon carbide stone set for hard steels (over 58 hRC)

silicon carbide stone for edge pro Grit:2500 Universal AngledGritomatic Sharpening Stones are used for sharpening knives using Hapstone or Edge Pro sharpeners. The stones are made of silicon carbide and are designed for the hardest steels (up to 65 HRC). All stones are 6 mm thick and mounted on high quality aluminum blanks with laser engraving. It is advisable to use silicon carbide stones for sharpening knives made of hard stainless steel or carbon steel. Using silicon carbide stones to sharpen knives made of