Herb grinder

Though the manufacturers claim they are intended for use with herbs and spices for cooking, they are often used to shred cannabis,[1] and are often unsuitable for actual use with spices (which instead are prepared using a burr grinder), resulting in a product that can be more easily hand-rolled into a "joint" that burns more evenly.

To increase the strength of aluminum grinders, they can be anodized, which a process that chemically alters the metal, making it stronger and less prone to wear.

2-piece grinders don't have holes in the main grinding chamber, and there is no storage section or kief collection tray.

3-piece grinders have holes in the main grinding chamber, and a storage section below the teeth for ground material to subsequently fall into.

Advertisements describing them as "spice grinders" have sometimes confused buyers who were unaware about the actual intended use.