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.

What is your end-goal?

End goal? What's that?

Why do you want to do what you are trying to do?

I want to use one of these adaptors to play the trumpet with a French horn mouthpiece, and try playing the french horn with a trumpet mouthpiece if they make such a shank. Will this adaptor work for it?

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.

why do you want to do this?

I want to play a trumpet with a French horn moutpiece, or vice versa.

why not just use the correct mp for each instrument

If I were to do that, that would be defeating the purpose, which is not to sound good or have the instruments range, but to avoid making embouchure adaption when I switch instruments. To answer your question. Not to sound rude, which this isn't intended, sorry if it comes across this way, but this topic was to ask get answers about mouthpiece shanks, not answer why questions. Thanks.