I’m a past drummer, but I’ve ever seen base drums like that. Looks like they have the ability to shorten and extend providing a tonal range. Pretty cool. Someone will buy it since it is unique and has been played many times in concert. That’s where the value is.
I probably should have said “pitch” range. I used to like Van Halen, but never saw this kit on MTV. I wonder if Alex Van Halen invented those adjustable base drums? Either way, it’s a cool concept where you can shorten the outer shell to the inner shell and have a higher pitch sound, and vice versus without having to re-tune the heads.