ISLAMABAD, April 7: The Central Board of Revenue has revised downward the rates of duty drawback on export of two different kinds of items. The new rates will be effective from April 7, 2004, said customs notifications issued here on Thursday. The rate of duty drawback will be 2.80 per cent of the fob value on export of magazines, brochures and books printed on coated art paper (all sorts); and 3.61 per cent of the fob value on export of plastic water-coolers (all sorts).