Belifu Dual Channel TENS EMS Unit 24 Modes Muscle Stimulator for Pain Relief Therapy, Electronic Pulse Massager Muscle Massager with 10 Pads, Dust-Proof Drawstring Storage Bag，Fastening Cable Ties… https://www.amazon.com/dp/B07Q32KX3J/ref=cm_sw_r_cp_tai_oqs8EbJDJ0Z9A

This is the one I have. I love it, lots of settings, easy to adjust the intensity, you can have multiple areas going at one time, long battery life, and it was only $36. I’ve had it for a year now, no regrets.