Cool 1 Metal Grinder Oil 420 40/4. Don’t feel like crumbling? This metal oil colored grinder is perfect for this. The well-known slogan “It’s always 420 somewhere” is engraved on the top of this indestructible grinder. This complete good looking grinder is 40 mm wide and has 4 layers. Included is a scraper to scrape out the remains of your weed. You don’t throw anything away.