Toshiba has announced that the small outline form-factor SSD drives that debuted in Apple's latest MacBook Air models last month are now available as a retail product. Dubbed the Blade X-gale SSD series, the drives offer a potential upgrade path for MacBook Air users, and may soon appear in other ultraportable notebooks.

Unlike many SSD drives, which are either packaged in a standard hard drive form factor or a special micro-SATA form factor for devices in which space is a premium, the new Toshiba drives are on a thin, small outline card similar to a RAM module.

"Up to this point, SSD designs also followed the basic design of small form factor HDDs, which does not fully leverage the capabilities of high density NAND technology," Toshiba VP Scott Nelson said in a statement. "Toshiba's module-based SSDs break with this approach, giving hardware designers greater freedom and flexibility in enabling their product design."

This design enabled Apple to make the MacBook Air thinner than previous models while leaving more room to be used for better battery capacity. There was some speculation that the new format was a proprietary Apple design, making upgrades for the company's new MacBook Airs impossible. However, the new Toshiba modules—available in 64Gb, 128GB, and 256GB—are the exact same modules used by Apple, offering a drop-in replacement (assuming you have the proper screwdrivers).

Taiwanese company PhotoFast has also announced that it will offer a replacement module that uses SandForce controller chips, known to be some of the fastest performing SSD controllers on the market.

In addition to being good news for MacBook Air owners, though, this announcement also means that other notebook vendors may adopt the new models in future ultraportable or netbook designs. If adoption is widespread, it could reduce the cost of such modules—which cost more than traditional HDDs—a benefit to both vendors and consumers.

That the Toshiba models appeared on the MacBook Air first continues a pattern set by Apple when the MacBook Air first debuted in 2008 with special small-outline processors from Intel. Those same processors were later made available to other notebook vendors after a short period of Apple exclusivity.