The water torture test (aka blender test)

[Stephen]

I certainly can't make any kind of "certifiable" claims of waterproof-ness, IP66, IP67, etc. However, I've taken every precaution possible, to ensure that heavy rain is not going to cause a problem for these lights. I feel pretty comfortable calling them "dunk" proof, but I wouldn't want to go so far as to say that you could use them under water.

http://www.youtube.com/watch?v=zsrSh5veYZk

[shark_attack]

Okay, but what is with the temperature? In winter months its very cold... its safe up to - 20 celsius?

best regards

[Stephen]

Yes, the colder the better for the light itself. It's the li-ion batteries in general that suffer a bit in the cold. They will have somewhat reduced capacity if they have "soaked" at the cold temperatures, but the main concern for you would be to make sure you never charge the battery at temperatures near or below 0 degC. This can actually damage the batteries.
Cheers

[shark_attack]

So, i cant use it for snowboarding because of the battery life time? I want to use it for night snowboarding this year... (MJ 880 & DS 500)

http://www.abload.de/img/snow14ze2p.jpg (http://www.abload.de/image.php?img=snow14ze2p.jpg)

best regards

[Stephen]

Wow... where was that picture taken?
You should be fine using any of your light systems in the cold (including the DS). The total run-time capacity of the battery may suffer a bit (maybe 10-20%) if the pack is cold-soaked at temperatures below freezing, but everything should still work fine. Believe it or not, I've used my DS headlight on Level 2 inside my sleeping bag while camping, and it made a great hand warmer (disclaimer... I actually DON'T recommend doing this, just for safety reasons, but it would definitely keep you from getting frost bite for a lot of hours in an emergency situation).