Belgium is complicated country.
For safe shipping, you should use EUB, which is limited to 2kg.
If you want to ship as much as possible, you should use DHL, which allows up to 4.2kg.
If you want to meet in the middle between efficiency and safety, EUB is still limited to 2kg, while DHL should be around 3kg.
added: 6/26/2023
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