Trombone Mouthpiece For sale: Willie's MUSE L5χ (Kai Metal, silver-plated). I tried it a few times, but I'm selling it to organize my belongings. It's very easy to play, so I think you'll be satisfied. It's been about six months since I bought it, but I've only used it a few times, so it's in very clean condition. Please feel free to contact me if you have any questions. Thank you.