The price of an external storage drive is tied to a few factors: the amount of storage capacity you’re looking for, how fast the drive is at transferring your files, and its physical size. At this point, high-capacity external drives that require power adapters are surprisingly inexpensive.

from https://www.theverge.com/2019/5/13/18518127/portable-ssd-external-thunderbolt-3-usb-c-samsung-x5-t5-specs-test-how-to
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