Wash 20 min at 100'F. Neutralize with 0.5% sodium bicarbonate for 20 min at 80'f. Wash 10 min at 80'f and 10 min at 100'F. Add: 3% sumac extract, 3/4% "Chembark" T, 3% "Leukanol" ND, 4/10% "Gantrez" AN-139. Run 30 min at 120'F. Add: % potassium oxalate, 1% formic acid. Run 15 min. Wash 10 min at 120'F. To upgrade side leather by imparting body and roundness, "Gantrez" AN is usually applied to the blue cream leather in a drum using the dry powder and common salt in a short float.