These can be used for anything or any project. You can use these at pet tags, keychain, for bracelets or necklaces. I love how smooth and flat they are. With these you can paint them, stamp them or even engrave them. You get 100 tags which will keep you busy for a long time. These would be perfect for any crafter you know or for anyone who makes jewelry. These are made from stainless steel and they are 10mm in diameter, 0.6mm thick, and the Hole at the top is 1mm. I received this product free in exchange for my honest review.