Valve
A Schrader valve consists of an externally threaded hollow cylindrical metal tube, typically of brass. In the center of the exterior end is a metal pin pointing along the axis of the tube; the pin's end is approximately flush with the end of the valve body.
Generally, all Schrader valves used on tyres have threads and bodies of a single standard size at the exterior end, so caps and tools generally are universal for the valves on all common applications. The core of the valve can be removed or tightened with a tool.
A new development is Schrader valve stems with integrated transmitters for tire pressure monitoring systems (TPMS).
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