This is an Adjustable Bottom Cap for euphoniums, supervised by Glenn Van Looy, a euphonium player. It has only been used a few times and is in beautiful condition. This product is compatible with Wilson euphoniums (※It could also be attached to Adams). It is installed on the 4th piston only. The bottom cap can be disassembled, allowing you to reduce the weight and change the resistance. For more details, please refer to the manufacturer's website below. https://www.heavybottomcaps.co.uk/product-page/glenn-van-looy-euphonium-abc The new price seems to be £78.95 + £17.82 shipping from the UK. (Approximately 19,300 yen as of October 30, 2024) #Euphonium #HeavyBottomCap #ABC #GlennVanLooy #Wilson #Adams