I bought this on ebay because it looked unusual and I paid less than $30 for it. Does someone know what it is? I'm not sure if that extra slide is to tune it to a different key or something from another instrument the seller is including by mistake. In any case I'm curious about the apparently large bore and interested in the challenge of getting the valves unstuck. If I can't make it work I'll stick it on board with some velvet backing and sell it as a decor iterm.