This heavy duty all aluminum 4 piece grinder is for serious smokers! Featuring magnet top for tight closure, 4 piece, 3 chamber design with mesh screen for fine pollen filtering. This ginormous grinder is crafted from a single piece of high grade CNC aluminum. These grinders receives a protective coating through "anodizing" which makes them virtually scratch resistant. The clear see through tops allows you to see and gauge how much you want to shred!