Our 2 piece metal herb grinders feature: One piece construction milled from billet stock. 63mm/2.5inches. Strong rare earth magnets. To top it off they are laser engraved right here in the USA by Tahoe Grinder Company! Unique designes and engravings which cannot fade or be removed make for a more personal buying experience; The customer is able to purchase something more taylored to their specific interests! Not to mention quality that lasts a lifetime!