Watch KnifeKrazy YouTube review of the new form-factor

The working position is below the pivot

Ultra-fine ceramic stones utilize the top quality 99

but it's not mandatory

boride am k stone for edge pro Grit:100 Watch KnifeKrazy YouTube review ofBoride Sharpening Stones are used for sharpening knives on Hapstone Pro sharpeners. Boride offers a wide range of stones with different performance values and different rates of wear. Boride stones are made of aluminum oxide, with the exception of CS HD series stones, which are made of silicon carbide. All Boride stones are 6 mm thick and are mounted on high quality aluminum blanks. Stones that are 6 mm thick offer a longer life cycle than stock Edge