"Our Chi is thinner than Air," said Jonney Shih, CEO of Asus as the Transformer Book Chi was announced at CES 2015.

If the name sounds familiar, that's because it was unveiled at Computex in June 2014, but now it seems there's a full family of Transformer Book Chi models. 

From Asus it's fighting talk: "more sophisticated than Air … clearer than Air … more powerful than Air", comparing the new flagship T300 to Apple's popular MacBook Air. 

Of course the Transformer Book Chi is a Windows tablet with keyboard, rather than a traditional notebook like the MacBook.

However, at the top end, the T300 comes with a sharp 2560 x 1440 IPS display, it has speakers engineered in collaboration with B&O and comes with the latest Intel Core M processor.

You'll get the choice of 4 or 8GB or RAM and a 128GB SSD in a tablet that is only 7.6mm thick and weighs 720g. 

But that's not the only model available. There is also the T100 and T90, offering the Transformer Book Chi at a range of prices and specs. The T100 has a 10.1-inch display, the T90 has an 8.9-inch display.

The Asus Transformer Book Chi will be available from February 2015. The T300 will cost $699, the T100 will be $399, the T90 is $299.