This Crystolon silicon carbide "Tradesmen's Stone" is a large specialty sharpening stone great for many multi-purpose uses, including for sharpening trimming knives & also for use as an abrasive file in many different industries. A red painted wooden handle is firmly attached to the stone for a solid grip when in use.

To obtain best results, lubricate your stone with genuine Norton Sharpening Stone Oil. Oil acts as an effective lubricant during sharpening to float away metal & abrasive particles that would otherwise clog up the stone. When metal particles clog the stone pores, it's called glazing & can ruin the stone.

From the Manufacturer:

Norton Sharpening Stones are made of the highest quality materials & are unequaled for long sharpening life, maintenance of shape & smooth cut.