The hydrogel electrodes used by Slender tone comprise a three layer conductive medium to deliver the electrical current. The electrodes, which have undergone rigorous safety and biocompatibility testing prior to entry into the market, are manufactured by Abelard (Fallbrook, USA), a leading supplier to the medical device sector. The double adhesive electrodes provide an excellent means to disperse the current over a suitable area thus preventing current build up and skin irritation. This is essential to ensure the user can increase intensities to maximum levels to attain the greatest possible training effect while maintaining their comfort. Nbsp;