Valve Stems Tubes 
Valve Stems Tubes, its what keeps the air in your tires, so this often over looked or ignored part of your tire maintenance can make a big difference on how reliable your tires perform.
Valve Stems
What is a valve stem, it is an extension from the wheel/rim that allows air to be regulated in the tire mounted to the wheel/rim, made of rubber the stem is flexible and has a cap to maintain pressure and protect the brass valve contained within the valve stem. Like we said above Valve stems are what keeps the air in your tires and allows you to add, reduce and in general regulate how much air is in your tires. It is common place on some vehicles to have in vehicle monitoring systems to keep you up to date on tire performance and warn of low tire pressure. It is recommended to change your tire valve stems with every change of tires or over a period of time.
Tubes
Most tires don’t have tubes in them today and tubeless tires are in most cases muck more reliable in day to day use.