But that card isn't just large, it's also tipped to be fast with read speeds of up to 160MB/s and write speeds of up to 90MB/s. Western Digital says that makes it more than 50 percent faster than current SanDisk Extreme UHS-I microSD cards. It uses the SD Association's A2 specification for laster launching of apps, too.
The card's design makes promises, as well. It's shockproof, waterproof, X-ray-proof, and can operate in a wide temperature range, from from a frigid 13 degrees Fahrenheit up to a burning 185 Fahrenheit.
Not surprisingly, you'll pay for the privilege of all that space in something smaller than a penny: The card will sell for $300. Compare that to the current stepdown "Ultra" 400GB model with slower transfer speeds that sells for around $231 on Amazon.
Samsung's iPhone X fighters.: Hands-on with
: All of CNET's coverage from the biggest phone show of the year.
Mobile World Congress 2018
reading•This massive, speedy 400GB microSD card will cost you $300
Apr 11•21 hidden Galaxy S9 and S9 Plus features
Mar 29•CNET UK podcast 537: Huawei goes colourful and Andy secures his home
Mar 25•Web Foundation CEO: Getting the whole world online is our goal
Mar 15•Galaxy S9 and S9 Plus vs. iPhone X, Pixel 2 XL