In short form, the box is a micro-sized PC specifically designed to sit under the TV. It’s also fully integrated with Steam, thus the “steam box” part of the name. The device is upgradable and comes with 8GB of RAM, a 3.2Ghz Quad Core chip and at least 128GB of storage.
However, Valve is not endorsing this product. It’s true that Valve is and has been looking into making a Steam Box of their own, but they’ve insisted it should be ‘affordable‘. The Xi3 Piston Steam Box comes with a neat price tag of $1,000, it’s understandable that they’re not endorsing the product or attaching their name to it.
If you like the idea of the Steam Box, you can now pre-order it and expect it to be released around Christmas.