I would like to tell you more about this.
It's a common mistake to think that it is a coin because you can read 20 L. (lire)
Well, this is a token/medal which follows the design of the real 20 Lire on the reverse (99% of the time not in the better way, in this coin for example you can see 3 little stars near "RA~" that you can't find in the real one). But on the obverse there's Mussolini!
Mussolini was the Prime Minister and he has never been king so he could not mint coins with his own image.
So you don't have to check weight to know that it's not a real coin.
BTW that's surely plated (same diameter but lower weight).