These handmade key chains are made from once fired 300 AAC Blackout ammunition. They have been cleaned & polished, a new 150 grain bullet inserted, and the key ring attachment soldered onto the primer pocket of the cartridge. It can be used as a key chain, zipper charm / pull, or the key ring removed and used as a necklace (we use lead free solder). The bullet/cartridge dimensions (excluding key ring) are; 2 1/4 inches x 3/8 inch. We have many other calibers and options available so please check our other listings. If you cannot find what you are looking for, please contact us. We may be able to make a custom one just for you.