i actaully used a french horn mouthpiece for the bowl on my first bong. I was under 18 at the time so couldnt go purchase a nice bowl and i just happend to have this french horn mouthpiece that i had no use for so i thought it was a good idea and it even worked for a little bit. I believe a french horn mouthpiece is a little bit deeper than a trumpets mouthpiece and i just unscrewd this metal tip from a pen and put it down for a little screen and it worked like a charm, but those days of smoking otta that have ended. But I did have some great times using that first bong i made.