myVolts Ripcord USB to 12V DC power cable is compatible with the Brother PT-E300, PT-E500, PT-E550W and lets you power the device from a USB port. Works with any USB port - laptop, phone charger, desktop PC, or even a mobile USB battery! It takes the 5V from a USB port and turns it into the 12V and amperage the Brother PT-E300, PT-E500, PT-E550W Label printer needs. .
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