Update: This deal has expired.

Ready for more digital storage space? Best Buy has Western Digital's Mainstream 1TB Internal Hard Drive on sale today for just $39.99, a discount of almost $15 off its average price.

Whether you're repairing or simply upgrading, the WD Mainstream 3.5-inch SATA Internal Hard Drive is a great option with a full terabyte of space and data transfer speeds of up to 6GB per second. It was designed for use with desktops and is compatible with both Mac and Windows computers. Best of all is its 7200 RPM speed, which is a decent upgrade from the 5400 RPM which standard drives have.

Western Digital also provides a free download of Acronis True Image WD Edition on its site so you can seamlessly transfer data from an older hard drive to this one.

This product has a 4.7 out of 5-star rating on Best Buy with over 2,500 reviews. A two-year warranty is included with your purchase.

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