No, data allowance is unlimited for both downloading and sending data.
However, the Japanese network provider used by our Pocket Wi-Fi imposes a “fair use” practice: There is a data download threshold of 10GB over 3 consecutive days. When overcoming this limit, the connection speed is reduced until 1p.m. on the next day.
Moreover, we ask our customers to refrain from browsing any website deemed illegal by French and Japanese laws, as well as to avoid any illegal downloading.