Valve Stem Caps

anyone know what these are used for? Just got (4) of them for free

Well, valve stems are the little spigots that let you put air in your tires (or let it out). Are they little screw-on caps for those?

How/why did you get them? :confused:

They keep a lot of the dirt and shit getting into the valve so its nice and clean when you add air to your tyres etc