26650 battery mainly served as power supply for high power laser flashlight ( blue laser pointer ). Generally speaking, laser pointers are divided into two types: low and mid output power( less than 500mW), high output power( more than 500mW ). The former lasers called laser pen while the other called laser flashlight. 26650 rechargeable battery is bigger than 16340 and 18650 battery. Of course, they own more capacity. Get high powered laser pointer at htpow, 26650 battery and a matched charger will come with your laser pointer.