Auvon via Amazon offers the Auvon TENS Unit Muscle Stimulator for $31.99. Coupon code "AOKECSQD" cuts the price to $21.75. With free shipping, that's $10 off list and the lowest price we could find. It features 2x2" self-adhesive reusable TENS electrodes pads, a USB cable, and adapter. Deal ends April 21.