is this normal?

i have crystal cases but their black not clear people tell me their dirty but there not the rubber is actually black and this makes my flowlights dimmer and its always wonders me if they are special or what? if you have the same please let me know or if you know whats up and i couldn't find anything like it online so i thought i would ask

No, they're not supposed to be black - they're translucent white, pretty much the same as the ones in the flowtoys pic here:

http://www.flowtoys.com/product.php?productid=72&cat=54&page=1

Where did you get them? If you bought them directly from flowtoys I'd be very surprised, if someone else is selling defective ones flowtoys would probably like to know.

Flowtoys will often give a 50% credit on defective stuff, I don't know what happens if you bought them from someone else.

I suggest you email

info@flowtoys.com

attaching a photo if you can and ask them about it.

They do go yellowish with time, but this has not affected light output. At least, this is my experience.

been using crystals since they came out, a slight yellowing after time, defo not black contact flowtoys with a picture methinks

my flow were gifts i was so happy to get em i didnt even think about the color of the cases till me friend told me his were clear and showed me and ever since its wondered me oh and thank all of you this helped "YES OH MY GOD!" -skrillex