High-quality brass construction with nickel plating ensures durability and corrosion resistance. Precision-engineered 21.3mm diameter x 45.2mm length design enhances valve operation accuracy. Suitable for professional euphonium maintenance and component replacement. Silver finish maintains instrument aesthetics while improving performance smoothness. Package includes 3 standardized buttons matching most vertical key bass systems. Note: 1.Please allow 1-3 mm error due to manual measurement and 1-3g weight error make sure you don't mind before ordering. 2.Due to the lighting of the photos and the difference of monitors, the pictures may not reflect the actual color of the real item. Please make sure you don't mind before ordering, thank you! About Shipping: 1.please pay attention to your delivery address such as: name, street, house number, doorbell/email without name, etc. is correct, or the order will not be delivered correctly. 2.All items will be shipped within 3 business days after the payment is received. Most times you will receive them within 8-12 days then. The specific delivery time is depend on circumstances. 3.During the shopping process, if you have any questions, please feel free to consult us, we will reply you within 801 hours Hope you have a pleasant shopping experience!