one-way valves

• checkOrder to pay
• backflowLiquid reversing course
• plungerSuction device for clogs
• diaphragmMuscle separating chest, abdomen
• flapOne-sided attached cover

hydraulic · pump · heart · veins · blood · flow · pressure · seal · rubber · pipe · drain · sump · aquarium · air · bellows · syringe · inflation · bicycle