Hi Mark,
Eventually i don't share eBay problematics, i am not even registered
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Well, you don't actually need to mount signallers; you just place them loose on a (reasonably) flat surface, and they stand upright by themselves. Having no projectile to be directed to a target, you convenientely fire the thing vertically, throwing the noise and flame up in the air. So they are either conical in profile, or (mostly) tend to have a widened (rimmed) base, to provide a certain stability. This is why often signallers (or noise makers) touch holes have a sort of lip or pan, where you deposit the priming gunpowder.
I hope i haven't spoken much nonsense, or Michael pops up and hits me
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Fernando
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