With one LED lamp,
With automatic voltage booster,which can change the voltage of two AAA batteries from 3V to 4.5V and give enough light.
THe efficiency of LED lamp is over 10 times of ordinary peanut bulb,so it has the functions of environmental protection and energy saving.
There are four multiplet for the lens,1.2X,1.8X,2.5X,3.5X.