Its called a Bamboo "Sax."
It isn't an actual saxophone, not being designed by Adolphe Sax, it basically is just a large bamboo recorder with a saxophone mouthpiece stuck to it.
If you want to by one, here's a great craftsmen who you could by one from, as well as other wooden flutes and similar instruments.
http://eriktheflutemaker.com/Bamboo_Saxes.htmEither way, an interesting instrument. My friend has one and its pretty cool.