A hot melt adhesive material dispensing system comprises two separate and independent rotary, gear-type metering pumps, or two separate and independent sets of pumps, which are able to output precisely metered amounts of hot melt adhesive material. The hot melt adhesive materials discharged are able to be independently outputted through suitable output devices onto a substrate to result in different outputted volumes of the hot melt adhesive material in accordance with predeterminedly desired patterns, or at predeterminedly desired locations. The hot melt adhesive materials may also have their volumetric outputs combined such that the discharged or outputted volumes of the hot melt adhesive material onto the substrate may be, for example, twice the outputted volumes of the hot melt adhesive outputted onto the substrate from only one of the two pumps, or from only one of the two pumps.