This grinder from Black Leaf with lifelong warranty has a nylon friction ring and a magnetic lid and is made of high-quality aluminum. The teeth are made of anodized aluminum for abrasion-freer grinding.
The herbs should not be grinded too finely when used in pipe bowls, but for vaporizers it can.
For cleaning the grinder, use alcohol or a special grinder cleaner. The grinder should not be cleaned in the dishwasher, as salts contained in the detergent lead to corrosion of the aluminum surface.