Orð dagsins eru tvö:

valve = Any of various devices that regulate the flow of gases, liquids, or loose materials through piping or through apertures by opening, closing, or obstructing ports or passageways.

throttle = A valve that regulates the flow of a fluid, such as the valve in an internal-combustion engine that controls the amount of vaporized fuel entering the cylinders.

throttle valve = a valve that regulates the supply of fuel to the engine

(tekið af http://www.answers.com)

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