I recently picked up a finger notch body and 1xAA extension tube from RMSK so I could use my eneloops in my older CP head. Three eneloops fresh off the charger reading 1.45v each provide an excellent beam- just as nice as a single 18650 at 4.12v. I picked up an extra AA extender and tried running 4 at 1.45- which should still put me at 5.8v- under the specified maximum drive stated in all of PEAK sheets of 6v. The beam was an angry blue and the output was far less than the 3 eneloops. Any thought as to what would cause such a result? I am fairly sure the new Cree's do not have the same voltage limitation.