Hard Drives - External

External hard disks are ideal for backup or portable file storage, and these drives come in a large range of categories: some use desktop-sized 3.5in hard disks, other use smaller 2.5in drives, and faster products use SSDs. Most drives use USB 3, Thunderbolt or eSATA connections, and these drives can come in different types of case – some are designed to be tiny, and others are ruggedized to stand up to dust, water and even fire.

Enclosure (1.8"-2.5") - SATA

These hard drive enclosures enable a 1.8" to 2.5" SATA internal hard drive to be converted into an external USB hard drive unit. Externally, these enclosures feature a USB 2 connection with some also fitted with an eSATA port, allowing a direct plug and play link up to a computer. Note that some of these enclosures are powered via their USB connection, with others using an external power adaptor, check specifications of the individual product to confirm.
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Enclosure (1.8"-2.5") - SATA - USB 3.0

Combining Super Speed USB 3.0 with a SATA hard drive interface results in an external hard drive with high data transfer rates. A 1.8" to 2.5" internal SATA hard drive fits into these enclosures. Power to these enclosures are either via the USB 3.0 connection or a separate power lead, check specifications of the individual product to confirm.
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External HDD 2.5" - 250GB - 4TB

These external drives use mobile 2.5in hard disks, which mean they're a lot more portable than desktop drives. They've got capacities that range from 250GB to 4TB, most use super-fast USB 3.0 and Thunderbolt connections, and many include backup applications and cloud storage deals for added security.

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External HDD 3.5" - 2TB - 8TB

These larger drives use desktop-style 3.5in hard disks, which means they're better suited to sitting on a desk than being carried around in a bag, but their larger profile does mean big capacities: some of these products serve up a whopping 4TB of space. Their 7,200rpm spindle speeds mean file transfer are quicker than 2.5in drives, too.

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