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 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. Not to be used for sea salt, wet salt, or dried wet salt or pink peppercorns. Measures: Height including screw knob 5.5"H, Base Diameter 2". Do not leave in prolonged direct sunlight.Wipe surface clean with a damp cloth. Do not immerse in water.