So I wanted to mail @Nenalyzed some Dutch TFIOS posters and postcards, and I thought I could reuse this Amazon envelope. Turns out it's 2mm too wide to be considered a letter, and shipping it as a package would cost about thrice as much.
I took a hobby knife, some duct tape, and now the envelope should be fine. Will ship it tomorrow instead. #stupidexpensivepostalservice
Btw, any other Belgians want any TFIOS posters/postcards?