They're each unipolar, meaning electricity flows from one to the other. As they're adjustable this can lead to all kinds of arrangements. You can attach one to your balls and the other to the head of your cock, or just side by side on that perfect spot you want to stimulate. The elastic fit makes sure that they're just as snug as you'd like them to be no matter where you place them. Placed at the base of the cock and balls a band can even be used as an effective and comfortable cock ring.They come readily compatible with any Tens Lead and directly compatible with the snap leads included with the Deluxe Digital Power Box. They're a great toy to combine with the deluxe digital power box.