This is a trombone mouthpiece. It is marked "48M." I purchased it about 30 years ago and used it for three years. Please understand that this is a used item and has been stored at home. I want to make this a pleasant transaction for both of us, so please ask any questions you may have beforehand. If there are no issues, immediate purchase is welcome. The price includes shipping. I am not offering any discounts. I will use simple packaging, but I will ship it as soon as possible. Shipping will be on weekdays. Thank you.