I recently came across this tire valve extension on a Mercedes forume and bought three of them. In case you haven't checked the tire pressure on your spare, it takes something like 10 minutes because the spare lays valve down in the well. So, you have to unscrew the hold-down, remove the jack and tool holder, and actually remove the spare from the trunk JUST TO CHECK THE TIRE PRESSURE! Needless to say, this is not something I do very often.

This extension hose allows you to check the tire pressure by just lifting the trunk floor trim.

Chek-a-spare, Check-a-spare, tire gauge guard

 

Great idea, it's not fun when your spare is flat when you are stuck on the highway

 

That's true , some car manufacturers just give you a tyre repair kit though