It is Fast system Fox #5xx, made in 2004. It is equipped with the standard keywork for a Fast system contra of that vintage, plus the F# trill key and right thumb Ab key. It is in excellent condition. It has the incredibly even, resonant, and clear scale of a Fast system instrument, especially in the upper register. It is the right instrument for a professional or aspiring professional player.
I am asking $39,000. This includes the instrument, one Fox bocal, and the original hard case in good used condition. It will also receive a service from Fox.
Here is a link to the issue of the Double Reed, with more information on Fast system instruments: