Large envelopes...

[Doris67]

Hello,
I know about Global forever stamps for SASE to Europe, but these stamps are for 1 ounce and for small envelopes.
can I use them (and how meny of these stamps) for a large envelope with 2 ounces to Europe?
there is no information on that in the lists of the USPS
or do I have to buy standard stamps to get to the amount actually stated in the list (USD 4,06?????)
thanks in advance for your support.