A metal smoking herb grinder is a great way to grind up your herbs for smoking. They come in a variety of sizes and styles, so you can find one that fits your needs. Some have a clear top so you can see the herbs being ground, while others have a solid top. These grinders typically have a few chambers - one for grinding the herbs, one for storing the herbs, and one for catching the pollen. Pollen is a fine powder that is produced when grinding herbs, and it can be used to make hash or edibles.