Non-gritty STAY-WET formula allows for prolonged use without re-application. Product of choice for ECG, TENS, monitoring and pediatrics. Non-irritating, hypoallergenic, bacteriostatic. Salt-free, no sodium ion transfer. Product of choice for conductive rubber / carbon electrodes. Spectra 360 differs significantly from all other electrically conductive media...it works by wetting the skin, thereby reducing skin resistance. Not recommended for defibrillation.