... hab ich mal gehört, keine Ahnung was da dran ist.

'Black Cat' ist ein Geschaeft, das 'fireworks' herstellt.

http://www.blackcatfireworks.com/

'fireworks' ist der Begriff dafuer, was man am 4. Juli in Amerika verwendet. 'black cat' ist ein Firework-Zeichen, das in bestimmten Gebieten gekannt und gelaeufig ist.

AE "banger" = Feuerwerkskörper. Explodes with a sudden loud noise.

laut Eintrag im OALD amerikanisches Englisch

Gibt's vielleicht Leute, die 'nen Böller "black cat" nennen, wie Klebestreifen scotch tape, etc. ?

Firecracker is the normal word for the kind of firework that makes a very loud noise and doesn't do much else. Fireworks is the more general term for displays in the sky at night.

Hajo: I've never heard banger used in this sense. I would have said it's mainly a slang BE term for (I think) sausage, or maybe a crude AE term for (I think) a (gang) rapist. Or conceivably a person in the habit of pounding on things like doors or walls.

David: Not to my knowledge; only jello, kleenex, scotch tape, xeroxes...

Chambers dictionary: Brit. 1. Slang. A sausage. 2. Informal. a. an old dedrepit car. b. (as modifier): banger racing. 3. a type of firework that explodes loudly.

This is a common term in the UK for this type of firework.

Ah, ein Experte. Bei dieser Gelegenheit: Was sind flares genau?

related discussion: flare - der Bengalo

banger = British English
firecracker = American English

flares are bright lights shot into the sky as signals, like boats send off when they're lost at sea.