Mast B1 WIRELESS TATTOO BATTERY: Super lightweight tattoo battery only 40g, compatible all RCA rotary tattoo machine. STANDARD RCA JACK AND LCD SCREEN: Digital 0.1v adjust tattoo power. SMALL SIZE AND LARGE CAPACITY: 2.7 4.2 2.2 cm size, 1,300 mAh of power to work 6-12 hours.
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