Although faster, cheaper solid state drives (SSDs) are winning marketshare and mindshare, makers of traditional hard disks are still working to squeeze more storage capacity inside standard 1-inch hard drive enclosures. HGST — known for its excellent G-Technology-branded G-Drives — today announced the Ultrastar He10, a 3.5-inch conventional hard drive with a staggering 10TB of storage space. But “conventional” might be the wrong word, as the drive manages to fit seven platters inside its hermetically-sealed enclosure, which is filled with helium rather than air, hence the “He” name. Measuring 1″ thick, it’s capable of fitting inside even the latest, thinnest Retina iMacs, as well as conventional external hard drive enclosures…

The Ultrastar He10 isn’t HGST’s first 10TB drive — that would be the Ultrastar Archive Ha10, introduced earlier this year — but the new model is faster for rewriting, and claimed to have a 25% longer lifespan. Ultrastar He10 is a 7200RPM drive with a 256MB data buffer, 5-year warranty, and a promised MTBF (mean time before failure) of 2.5 million hours — the type of extended longevity expected of HGST’s server-grade drives. It also promises an average latency of 4.16ms, with sustained transfer rates of 249MB/second (read) or 225MB/second (write), and 8ms seek times. HGST is offering it in 8TB or 10TB versions, as well as with SATA-III or SAS interfaces. HGST hasn’t announced pricing, but a report from Ars Technica suggests that the price will be approximately $800.