Precision metering instrumentation needle valves start, stop, and throttle media flow in sampling systems and instrumentation panels, and have a fine stem to provide more precise control than standard instrumentation valves. The position of the needle-shaped plunger relative to the seat within the housing determines the flow rate. Flow increases as the valve's plunger is lifted away from the seat and decreases as the plunger is lowered closer to the seat. These valves are compact and suited for high-pressure applications.