This is a free file storage space from Japan, no registration is required to use, you can upload files in batches, online package into a single compressed file, and password protection function, the default can be downloaded 20 times. The file storage time is not specified, it should not be very long. During the pandemic, the file size has increased from 10 GB to unlimited (single file 250 GB), and the file storage time has been extended to 65 days.