Presta valve

A Presta valve shown in context of the rim, spokes, and tire of a bicycle wheel
A closed Presta valve

The Presta valve (also French valve (FV) or Sclaverand valve) is a type of tire valve commonly found on high pressure bicycle inner tubes and is commonly used on tubeless setups. It consists of an outer valve stem and an inner valve body. A lock nut to secure the stem at the wheel rim and a valve cap may also be present.