So, since everyone is asking "How can I tell if my HDS is a 4000, 3500, 3000, or 2700k? There is nothing written on the light and only on the packaging!"
You can't... or can you?
It is written on the power supply. IF you take the bezel and reflector off, DON'T touch anything in there. The elf is a tricky one and will use any excuse to run out of the light and disappear and would like nothing better than for you to start messing with the emitter... his window to escape!
NC40= Nichia C 4000k.
Oh, and look! The boards are... WHITE!
Thanks for the info....you put our fanatic minds at ease.