The piston has some looseness. I have no knowledge of musical instruments, so I have not confirmed its operation. As this is a used item that has been in someone's possession, please refrain from purchasing if you are sensitive. I have posted many photos, but please understand that there may be scratches and dirt that cannot be conveyed through the photos. No claims, no returns, no refunds. It will be shipped by wrapping the dedicated case shown in the photos with cushioning material such as bubble wrap.