Hi,
So if sda1 is your boot partition, then sda is your hard disk in general.
If you don't have any other scsi devices then I'd guess your usb will show up as sdb1.
If you do have other scsi devices go up the alphabet one for every scsi device you have as a first guess, theres only one useful partition on your pendrive so the number should always be 1.
People have discussed how to find out which device it is on these threads, but I found it quicker and easier by trial and error - but then first guess was correct for me

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