Sharpstone Vibrating Grinder 2.2″ 4 Piece Aircraft grade aluminum rod CNC machined herbal grinder Vibration featrure Sharpstone Grinders are a high quality herbal grinder made out of aircraft grade aluminum rod. They are CNC machined ensuring that no glued in teeth. Each herbal grinder is also individually anodized to make sure scratches and smudges are less likely to occur. The teeth on Sharpstone Grinders were manufactured to be diamond shaped with razor sharp edged. You get a perfect grind down every time making the desired blend the perfect consistency for vaporizing or cooking. The lid is reinforced with an ultra-strong double magnet for an air-tight hold. Your blend will never fall out! The 4 piece grinders have an additional stainless steel pollen screen that is extremely durable. This helps produce the ultimate amount of pollen from each desired blend. Additionally, this specific grinder has a built in viabrating mechanism that helps shake even more pollen into the pollen catcher. Every grinder is accompanied with a carrying bag and pollen scraper.