Rufly does not provide a truly unlimited data eSIM for Belgium. Every package listed for Belgium carries a fixed allowance of 500 MB per day with a reduced speed of 5 Mbps thereafter, and once a total of 30 GB is reached the speed drops further to 512 kbps.
The available alternatives are fixed‑data plans such as Belgium Unlimited 7 days, 15 days or 30 days, all priced between $25.76 and $56.00 USD. These plans offer a predictable data allowance and may be more cost‑effective than paying for high‑volume usage on a pay‑as‑you‑go model, unless the traveller is an extremely heavy data consumer.