This is currently the cheapest way to get a 4TB hard drive for a PC, storage server or a NAS…etc. It's far cheaper than any Hitachi 7200rpm 4TB internal drive.
It will have to be removed from its external enclosure, which is done here - https://www.youtube.com/watch?v=morhgz2OU_g
It is also available at mwave, PC case gear, Umart…etc. http://staticice.com.au/cgi-bin/search.cgi?q=hitachi+4tb&spo…
It's not a sale, but I think it's a bargain given how many people are in the market for 4TB internal drives.
Really?
… and then there's this and this