Durasole is an aldehyde-based sole dressing formulated to harden the equine exfoliating sole and frog.  It is extremely effective in enhancing the protective capabilities of those structures and does not affect the proximal sensitive sole or frog.  Durasole works by swelling and thickening  the cell membranes of the exfoliating sole, not by coating the sole with impermeable oils. Durasole does not contain copper napthenate or any essential oils. Because of its unique formulation, Durasole can be used for extended periods of time on chronically thin-soled horses without fear of drying out the foot as it does not compromise the moisture balance of the foot when used as directed. Durasole creates a tough, natural, pad between your horse's sensitive sole and the world's often hostile environment.