The Carbon Hunter is made from Carbon Fiber and has a beautiful elk antler inlay. Because my rings are made with Antler colors can vary. Antler can be darker or lighter than the photo. This ring is great for firefighters and emergency crew that need a ring to be cut in the case of an emergency. Millimeter varies depending on size of ring. Can be made in sizes 6-15. If a bigger size is needed please email me. All sales final.