Zagall offers the Aluminum 3.5″ External Serial ATA USB 3.0 Enclosure for $19.99 with free shipping. That’s among the lowest total prices we’ve seen for any 3.5″ USB 3.0 hard drive enclosure. (It’s also $8 under the lowest total price we could find for a similar enclosure elsewhere.) This can be used with 3.5″ Serial ATA hard drives up to 2TB.