Be sure to read the instructions. I read all the reviews about the instructions being missing so I didn't read them. It took me ages to get it working because I didn't read the instructions. Either everyone else hasn't read them or the instructions have been updated. It's very easy. Green for reception, blue for transmission. To toggle, press and hold the small button for 4 seconds. In the mode you want, press and hold the big button until it turns off. Then press and hold the big button until it flashes quickly, which means pairing mode. You can then connect your device. Worked in less than 30 seconds if I followed the instructions.
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