Solidrock&reg; Four Piece Herb, Spice or Tobacco Pollen Grinder, 42 mm diameter Super sharp, well designed, correctly placed teeth for the best grind, does not rip or shred Powerful Neodymium magnets keep the lid on and leftover herbs fresh and odor free Textured sides on the lid give the best slide free grip when grinding your herbs Balanced weight, correct size and thickness of grinder and teeth Tough and reliable, lasts forever.Silent Grind, smooth and quiet