Cali Crusher Homegrown 4 Piece Grinder NEW Patented Dual-Action, Radial Cut Teeth NEW Patented Quick-Lock Threads Made in the USA Cali Crusher Homegrown Grinders are a new high-end brand of grinders, made in theUSA. These grinders are based out ofSan Diego,California. They come in one size, 2.35" wide by 2.25" tall. Each grinder is manufactured from 6061-T6 aerospace grade aluminum. They are sturdy and ready to take on the heaviest of grinds. The latest in patented technology was used to design the teeth and threading system used in this grinder. The teeth have a new patented dual-action, radial cut teeth. They create optimal shredding power when faced against large loads of herbs. The threading system of the Cali Crusher Homegrown Grinders is also patented. Each grinder has a quick-lock thread system. It is like nothing you have seen before. It was made to make getting to you herb quicker and easier. The less hassle the better. You also never have to worry about any mis-threading or your grinder getting stuck. Cali Crusher Homegrown Grinders have many other desirable features. They use Neodymium rare earth magnets for a super seal closure. Be ensured, your dry herbs will always stay fresh with this strong hold. Another awesome feature is the removable screen. No more worrying about your screen getting damaged. They are easily replaced. It comes with a 210 micron count screen in place. It allows you to catch the finest of pollen, but if you prefer something finer or courser, no problem. All you have to do is switch it out. Each Cali Crusher Homegrown Grinder comes with its very own OMG! pollen scraper. They are available in a wide range of vibrant, matte colors.