Roland AE-20 AE-30 Digital Wind Instrument Octave Key Upgrader Modification Accessories Extended Key Length Adjustable Electric Saxophone Octave Key Travel DIY Flat Keys

Standard Version: High cost-performance ratio, consistent performance, suitable for all types of music. Standard Version: High cost-performance ratio, consistent performance, suitable for all types of music. Extended Version: Equipped with a newly developed pressure plate, enhancing the operability of the double treble and double bass keys. Powerful and comprehensive in function, suitable for all types of music, also user-friendly for users with short fingers. Treble Key Version: New customers should not purchase this version. It is specifically developed for playing music with many double treble or double bass keys, with a limited scope of application, only suitable for experienced customers upgrading their skills. Product Design Intent and Function: 1. The octave keys on Roland digital wind instruments are designed with an outward arc shape, resulting in the thumb's movement trajectory as shown by the red arrow in Figure 2. This causes the thumb to need to extend to the right to reac