3M™ Flexible Diamond Whetstone 6220J is a metal bonded flex diamond glued to an aluminium base. Our 6220J whetstones have an open dot pattern for durability and long life, when allowing performance to contours.For precision faceting and sharpening of chisels, blades, knives and carbide tools use 3M™ Flexible Diamond Whetstone 6220J. Our 6220J whetstones