Large LCD & Multi-Modes. TENS + EMS Unit. 4 Channel (A1, A2, B1, B2). The independent A/B channel can work in different modes and different levels of intensities (e.g. you can select mode 7 with 3 intensity for your shoulders in channel A1 and A2, while in channel B1 and B2, this TENS machine can work as a back pain relief products in P3 with a much stronger intensity. ).
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