Les - Thanks for the edit comments. It never crossed my mind to move the 6P head with that 300 lumen LED module over to the SolarForce battery tube. Hmmm -- more experimenting ....

BTW, I find the 300 Lumen level to be a sweet spot. It takes a lot more Lumens and battery energy to get an appreciable illumination effect. In many cases much less light is plenty. That's the reason I'm going with three 18650's with the K3.