The mill is made from solid Rubber wood fully FSC certified, finished with 8 coats of high gloss lacquer hand polished between each coat. Using a ceramic grinding mechanism, the mill requires a clockwise motion to activate. The mills can be used for grinding either Rock Salt (Dry Salt Crystals) or Black Peppercorns. Wipe surface clean with a damp cloth. Do not immerse in water. Measures: Height including screw knob 9.5", Base Diameter 2.75"