I was looking for a Trumpet to French horn mouthpiece adaptor or shank as well as one for French horn mouthpiece to trumpet. I came across 2 links on wwbw (Woodwinds and Brasswinds) that had two results. Link 1: Bach Mouthpiece Extensions and Adaptors - LOW PRICES at WWBW Link 2: DEG French Horn to Mellophone Mouthpiece Adaptor - LOW PRICES at WWBW It looks like the second one would let you play the trumpet with a french horn mouthpiece. And the first one looked like you could play trumpet with a cornet mouthpiece (which wouldn't be bad). The questions I was wanting aswered were what is the difference between the two links's adaptors, I know the first one you had different options. Does a mellophone take the same mouthpiece as a trumpet, or cornet? If I want to play on a trumpet with a French horn moutpiece, what should I get? If I want to play the French horn with a trumpet mouthpiece what should I get? Do some of the adaptors for for adapting more than one instruments mouthpiece into more than one instrument? Are trumpet, french horn, cornet, and mellophone all different sizes (I know at least two of them are). If you could answer all of those questions I'd really appreciate it. Thanks.