Camera Filter Cases Good Quality, Rather Bulky IS There Any Way To Adjust Or Filter An Off Camera Flash Unit, To Emit A UV Or Blacklight?

IS there any way to adjust or filter an off camera flash unit, to emit a UV or blacklight? - camera filter cases good quality, rather bulky

I think, but I wanted some advice. Looking for something easliy portable neon effect for some materials. He lights BlackLight's business, but something wouldnt mind a laptop bag.