ENDUR-C 500mg with Rose Hips sustained release. Combines high-potency vitamin C, ascorbic acid, with our vegetable wax matrix technology delivery system. Resulting in a slow and steady release of ascorbic acid over 5 to 7 hours. By releasing small amounts of vitamin C at a time as the tablets travels through the intestine, ENDUR-C allows your body to slowly absorb vitamin C. In this way it not only helps maintain optimal blood and tissue levels but avoids excell loss in the urine that is typical of regular forms of high-dose vitamin C.