This is the Comandante Burr Care Set. COMANDANTE BURR CARE FLUID This is a care kit for the stainless steel burrs of your grinder. Apply a small amount of oil to the cloth and rub it on the burrs of the mill. Then, use the brush to remove dirt from the surface of the burrs, and finally polish with the cloth. By doing this, you can prevent the deterioration of the burrs and maintain a smooth grind.