Barrel for playing an E♭ clarinet with a B♭ clarinet mouthpiece

This was sold by Ripekan.
Purchased on August 25th.
You can play the E♭ clarinet with a B♭ clarinet mouthpiece. The tone becomes closer to a B♭ clarinet, losing the harshness characteristic of the E♭ clarinet, and making high notes much easier to control.
It has only been used a few times for testing the sound, so it is in beautiful, almost unused condition.

Below is a copy of the description from the sales site:

This is a barrel for playing the E♭ clarinet with a B♭ clarinet mouthpiece. Made of grenadilla wood. There may be some difficulty with intonation in specific ranges.
This barrel is designed to connect the mouthpiece (for B♭ clarinet) and the upper joint (E♭ clarinet) as directly as possible. Depending on your instrument, there may be small gaps between the mouthpiece and the barrel, or between the barrel and the upper joint.

Photos 3-6 were borrowed from the sales site.