Tribulus terrestris is the #1 selling testosterone booster, and the best example of a supplement that increases libido, but has no effect on testosterone.
Ab belts may cause muscle contractions if used properly. But the belt alone cannot produce six-pack abs. The real challenge to ab definition is the layer of fat that lies right under the skin, hiding muscle tone.
4 Customer Reviews. These Goodyear Gatorback Poly-V serpentine belts run quieter, stretch less, and transfer more power than other belts. As they warm up, the composite construction between the cords and rubber compound becomes more efficient at turning your engine's accessories.