Note 1: As these are constructed of styrofoam, there's a good chance the cone will crack in half after being used (proving that it has done some work for you). If you fly often, you might wish to have a few cones available to replace those that break andare beyond repair.
Note 2: Many players will wrap the cone in a soft cotton sock where it touches the bell to avoid marring the horn's finish.
Note 3: While bell cones like this have been used for years by travelling professional musicians to prevent damage to their instruments, we do not in any way whatsoever make any warranty or guarantee, implied, indicated, or otherwise, that using a bell cone will be effective for you. We will accept no liability for damages of any kind whatsoever. Use at your own risk.
Note 4: These cones are generally readily available from your local craft store. We buy them from a local store and mark them up, but you can probably get them somewhere close to you for less. They are offered here as a convenience for those who cannot or don't have access to a local craft store.
Note 5: And finally, please never never place clothes, towels, or other wadding in front of your bell in a case when travelling. The wadding only serves to physically connect the bell flare to the front wall of the case, where any impact energy is then transmitted directly into the bell flare, often causing a crease or other ugly damage. There should always be an air gap in front of the bell, hence the use of bell cones like this one.
-cdp