Help identifying a part on a L72
 

You should confirm with someone else, and possibly post a couple pictures from different angles (hard to see with those shiny valve covers reflecting), but to me it looks like (don't know exact name for it) part of the pcv system. should attach to the bottom of the air cleaner housing. You can also retrofit it with an airfilter for a "cleaner" look.

google: PCV system and learn what it is and how it works. I had these same newbie questions when i got into this hobby and the hunger for more knowledge and understanding of the car and motor seems to never stop.

-Good luck!

I would agree with this. You don't specify what year of car, but the attached pdf from the 69 AIM shows what I believe is the correct part identification.

The PVC is the one on the drivers side to the carb, that unhooked hose is the breather hose from the air cleaner to the crankcase to let air in as the PVC draws vapors out of the crankcase. You can replace it with a breather cap if you don't want to use an air cleaner set up with a fitting for it. Something like this but there's a bunch of different styles available that simply push in the hole. https://www.jegs.com/i/Spectre/865/4...yABEgL1OfD_BwE

Y2K is spot on. If you go to a push on breather, the valve cover grommet might need to be changed also. Some come with a grommet.

Thank you all for the help, sometimes it gets difficult to translate the correct name to English :)

That's definitely the breather hose from the air cleaner to the crankcase. The air cleaner base doesn't have an open insert for the hose (?). Check attachment please.

I can definitely open it and insert the hose, can this be done without creating a problem?

You should be able to open the pre-cut holes in the base of the air cleaner housing. But, you will need a PVC hose fitting like this : https://www.summitracing.com/parts/spe-4960 . Just make sure that the PVC fitting base has a good seal, to protect your engine from unfiltered air.