The K - Range lights implement the latest generation Cree XM-L2 U2 LEDs. They are also equipped with the most advanced super high density Panasonic NCR18650B Li-ion batteries.
These lights are therefore capable of better runtimes, weigh less and shine brighter than any other cycle lights on the market.
The Cree XM-L2 LED delivers breakthrough lumen output and efficiency, the XLamp XM-L2 LED is the highest-performing, commercially available, single-die LED. Built on the SC³ Technology Platform, the XLamp XM-L2 LED delivers up to 20% more lumens, lumens-per-watt and double the lumens-per-dollar of the original XM-L (www.cree.com).
The Panasonic NCR18650B cells boast an impressive 3400 mAh capacity. In comparison to the 2200 mAh of standard Li-ion cells, this explains why a 4 cell Panasonic battery pack can out perform a 6 cell standard battery pack (www.industrial.panasonic.com).
At the end of October 2013 it was decide to make the K - Range official. Before then the Extreme 2k did not have the Panasonic battery packs, the package was revised and now includes them. This effectively extends the runtime of the light by 40 minutes to 4h on high, while reducing the overall weight by 100g.