The Schrader valve is a valve stem invented by August Schrader and is used on virtually all automobile tires and wider rimmed (lower pressure) bicycle tires.
It is a poppet valve assisted by a spring. Schrader valves are also used on the fuel rail of some direct fuel injection engines and on some automotive air conditioning systems, in a diameter larger than those used on tires, to allow recharging with refrigerant. In addition, Schrader valves are sometimes used on irrigation systems to provide a place to temporarily attach a portable pressure gauge.
tire tube valve