In fluidics, forces in vehicles occur via circulation control,[clarification needed] in which larger, more complex mechanical parts are replaced by smaller simpler fluidic systems (slots which emit air flows), where larger forces in fluids are diverted by smaller jets or flows of fluid intermittently, to change the direction of vehicles.[5][6][7] In this use, fluidics promises lower mass, costs (up to 50% less), and very low inertia and response times, as well as simplicity.[citation needed][clarification needed]