Two screens one for the bottom and one above that gap attached to the top part

4 ounces seems to make it too full, probably 3 ounce

just for a tiny espresso

This is for sale internationally.

On the Vintage BIALETTI 12 oz:

bottom is marked "Made By Bialetti" 

N38 since 1933 

with the man logo and 

Italian Quality below the man

It is very old and missing the little cap on top of the bubble-up spout

   but there is a substitute aluminum foil replica of the one on the little coffeemaker

   the middle seal is in good shape and so are the two screens

   some mineral deposits in the very bottom of the base, 

   as you can see it is dark inside mixed with some 

   coffee residue, you may soak all in vinegar then wash

California has very high mineral content in the water.

Imperfections in the aluminum due to age and slight water staining you can polish them if you do not like the patina