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 faster 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.
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