A Mellotron is an odd duck. One of the first sampling keyboards, this mechanical beast used loops of magnetic tape to play back certain sounds with each keypress. Well, it turns out there are billionaires willing to spend, well, billions on refurbished see-through Mellotrons.
The monstrosity you see before you was featured in the Robb Report and may be the ugliest yet most expensive primordial Casio keyboard in the world.
The Skellotron see-through Mellotron [MusicThing]