These are replacement screws for Sako optilock rings. They are stainless, and use a T-10 torx driver. Included are 10 screws (so you will have two extras). I am selling sets of 10 screws for $20 shipped within Canada. Same stainless screws but chemically blackened available for $25 for a pack of 10 screws delivered within Canada Shipping to other countries is available, but will cost slightly more - private message me for details.