22.5W Transparent Mobile Power Bank Case 4*21700 Battery Box PD Fast Charging

In addition the product does not support modification, welding. If the use of non-compliant batteries are not responsible for after-sales. The motherboard is retrofitted with an anti-reverse connection chip, installing the reverse does not burn the motherboard, but due to the spring shrapnel is one piece, the battery broken skin, battery short-circuit, a positive and a negative, series connection will cause the burn spring, but re-installed correctly, the motherboard can always be used normally, will not burn.

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