The NiteCore D20 is the first 2x AA SmartPD flashlight.
Dimensions: Total length 154mm; Bezel Diameter 25mm; Tail Diameter 23mm;
Battery: powered by 2 AA batteries (including 1.2V AA rechargeable batteries - NOT LITHIUM-ION)
Output & Runtime
Maximum output is 180 lumens for about 1.5 hours (then the brightness declines to 50%)
Minimum output is 2 lumens (1%) for about 150 hours (then the brightness declines to 50%)