18650-battery-holder-dat

Plastic houseing battery holder

3X AA battery holder

== 1.5*3 = 4.5V

2X 18650 battery holder

== 4.2*2 = 8.4V

• 2S-lithium-battery-charger-dat

4X 18650 battery holder

== 4.2*4 = 16.8V

ref

• battery-dat