via this listing
Additional Retro Gear Shop Listings
"For sale is a very rare Floyd Engels Theremin Cello with custom tube amplifier. It's in excellent shape and fully functional. This is a modified replica of Leon Theremin's Stringless Cello from the mid 1930's made by Floyd Engels in 2011. Apparently only 10 of these were ever made, you aren't likely to see another one for sale again, grab this unique piece while you can!"
