A grinder is the least glamorous and most consequential accessory you own. Evenly ground flower burns evenly, packs consistently, and vaporizes properly — hand-torn buds canoe in a joint and scorch in a dry-herb vape.
2-piece: two halves, grind and go. 3-piece adds a collection chamber so ground flower drops out of the teeth. 4-piece adds a mesh screen and a kief catcher underneath — over a few months that catch fills with trichomes worth sprinkling on a bowl. A 4-piece is worth the extra few dollars for that reason alone.
Anodized aluminum with diamond-shaped teeth is the durable default. Avoid cheap zinc alloys, which shed flakes. Wood grinders look better than they work. Grip ridges and a magnetic lid matter more day-to-day than tooth count.
Coarse for bongs and pipes so airflow stays open. Medium for joints and blunts. Fine for dry-herb vaporizers, which need surface area to convect properly — but not so fine that it pulls through the screen.