【Product Name】 ★ Mark Curry Light/Heavy Bottom Cap for Yamaha Trumpet 【Description】 ★ This is a new part purchased from an authorized online shop in Japan. ★ The package has markings for both YAMAHA and STOMVI, but I don't own a STOMVI trumpet, so I'm unsure if it's compatible. ★ Weight is approximately 28.2 grams (see image). ★ I tried it on a current model Yamaha 4335GII and felt a moderate resistance, resulting in a thicker sound (this is just my personal impression). ★ Although it's a bottom cap for Yamaha trumpets, compatibility with all Yamaha trumpets may vary depending on the model number and year. Please be aware that you are responsible for any damage to the screw threads or the instrument itself if you force the installation, and no warranty or refunds will be provided. ★ We will ship quickly and carefully via Yu-Yu Mercari Mail from the post office.