How to access USB connected through FTP

I try to copy large videos files from my computer to the USB attached HD on my Vero 4K.
I can connect with FileZilla and can see the file structure of the Vero 4K, but I don’t see the USB attached.
Can you help?

It should be automounted in /media

Why is the transfer really slow? I stuck at 370Kb/s. I thought FTP was faster than SMB transfer (1MB/s) and I am local

Not in my experience.

Make sure you’re using FTP and not SFTP. Some clients default to SFTP.

With FileZilla SFTP I get around 9 MiB/s throughput uploading a file from PC to an USB connected external ext4 formatted HDD at the Vero 4k.
If @Fab_Rizio only gets 370Kb/s(???) (I hope he means 370kB/s and not kbit/s, see correct syntax here) there must be other circumstances involved like WiFi, etc.

By changing to FTP, I go to 1 MB/s… but cannot reach the 10MB/s people are writing here

The reason for that is your powerline adapter nothing the software can do about.