Features: Mouthpiece is made of copper alloy material, which is enduring and has a simple appearance. The mouthpiece features small shank and is a 12C type,there is mark on the surfaces to makes you can easily identify. The sound of this mouthpiece is pure and suitable for most altos trombones. The compact shape is easy to carry. Suitable for beginners and professional trombone players. The mouthpiece can make solid and rich sound,is easy to install and disassemble. Specifications: Material: Copper alloy Color: Gold/Silver Size: about 79.3x38mm/3.12x1.5inch Package Includes: 1pc 12C altos Trombone Mouthpiece note: Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. Due to the difference between different monitors, the picture may not reflect the actual color of the item.