The Pulsar Concave Rainbow Anodized Aluminum Grinder is 2.5 inches in diameter and features a chameleon-like metallic rainbow finish that constantly changes in the light. The concave lid is perfect for holding herb while loading bowls and pipes, and the shape of the grinding chamber funnels herb towards the center for a smooth, easy grind. These quality grinders also have diamond shaped teeth for shredding herb, a pollen chamber with sifting screen, magnetic lid, and scrape tool.