Some are colorful, some are not. Some are very small, and some are quite large. Some have stickers and skulls, some can also be used as smell-proof jars. Some grinders, you can just tuck in your wallet with no one the wiser. Some are metal, and some are plastic. Some are even automatic. There are grinders with no decoration that you can dress up however you’d like.
The great thing about grinders is they are perfect for add on and last-minute sales. Every time your customer buys a pipe, water pipe, dugout or vaporizer they will need a grinder. It’s a necessity for the hand-rolled smoker as well - you must grind the herb or loose-leaf tobacco before you can roll it up. Grinders are something you don't want to be without.