Thank you for viewing. I opened it for photography, but it is a new, unused item. I accidentally bought two on Amazon, so I'm selling one. I use it for a flugelhorn, but it's originally for a trombone. Features of Okura + Mute (from the official website): - Suppresses unwanted vibrations and cuts uneven sound. - The body can be opened and closed to keep the inside clean. - Choose from two sizes of air holes. - Allows practice using different levels of resistance. - Brand: okura + mute - Color: Black - Type: Trombone mute