A product dispensing system comprises a calibrated nebulizer having a nebulizer jet, mouthpiece, means for sourcing compressed air, a manifold for distributing the source of compressed air in at least one direction, a nebulizer accommodation means which is accessed by port, and a valve means for controlling the manifold and thereby the flow of compressed air to the port. The manifold and the port are linked by a length of tube, wherein the internal volume of the tube from the manifold outlet to the nebulizer jet is less than 0.7 ml.