3.7V Li-ion batteries: 32650, 26650, 26500, 25500, 22650, 22500, 21700, 20700. 4 slots support up to 21700, the middle 2 slots cannot support 26650. 18700, 18650, 18500, 18490, 18350, 17670, 17650, 17500, 17350, 16650,16340(123A).
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