Thank you for viewing. This is a Rondino Mag Top Button for tuba pistons. These piston buttons are made of magnesium and are from Prima Gakki's private brand, Rondino. They were used for about two years, so there is some dirt on the back of the buttons used for the 1st and 2nd pistons, which are used the most (red circle in photo 2), and there is also some slight coating peeling on the front, although it's not very noticeable (red circle in photo 3). Therefore, please refrain from purchasing if you are concerned about this. These Mag Top Buttons are very light and I felt that they significantly improved operability and also changed the tone. The following is a quote from the website: The world's lightest and fastest finger action! The Rondino Mag Top Button (piston top button for tuba) made of magnesium alloy with a special coating finish weighs approximately ¼ of the original. By installing it, not only does the operating performance improve, but also the sound leaps and connections become smoother, and the pronunciation becomes clearer. Material: Magnesium alloy, special coating finish Specifications: Weight 3.3g Screw length 8mm Screw diameter Ø4mm Screw pace 0.7mm. [Compatible manufacturers] bm, B&S, Meinl Weston, Besson (※Some models are not compatible). New price: 34,100 yen (tax included) ※I have not tried it on YAMAHA, so I cannot answer whether it is compatible. Also, I cannot answer questions about whether it is compatible with specific instruments from compatible manufacturers (e.g., is it compatible with Meinl Weston 5450?) because I have not tested it myself. ※Although not mentioned, I used it on a Hirsbrunner C tuba, so I think it can also be used on Hirsbrunner tubas. (Please note that it may not fit depending on the year, so I cannot guarantee that it will work.) ※Please note that returns are not accepted for items that are not compatible after purchase. To avoid any problems, please leave a comment before purchasing. #tuba #tuba #piston #piston button #wind instrument