need help identifying!

[lin7310948]

i was going through some of my porsche 911 stuff and found a red in color cylinder with german directions for use. the cylinder has a very short hose attached....it is in good shape with the original wire and seal in place. it seems to be something to do with tire inflation. i know that it came out of an early ...longhood...but do not know what it is called...it will be for sale if it is of value and i can provide a couple of pictures...thanks