I have one in emerald green.
There is nothing mechanical, just holes like a recorder. Intonation can be tricky, and it takes practice to get a feel for half-covering holes for sharps/flats and bending notes. But it is fun and very easy to carry around. As for the price, $75.00 for the molded models seems a bit steep, but the material is high quality, not thin plastic tubing. The finish is very nice. So for a product that is surely limited in potential customers, I don't think the price is unrealistic.