I used this button to replace a lost one on an old stagg trumpet, wich worked out perfectly.
Fitts perfect and is also very beatifull, it is slightly bigger thicker then the other two, so i put it on front fir my ring finger, wich works out even better snd feels more natural too.Also nicely build and sturdy , so you cant play without, welk ya can bud.. you know. Very well worth the money. Thanks