From Manufacturer
The 64GB Professional 2000x UHS-II SDXC Memory Card from Lexar features a storage capacity of 32GB and takes advantage of the UHS-II bus to support advanced DSLR functions such as continuous shutter bursts and rapid shooting, as well as raw and JPEG captures. This card is also well-suited for video capture, including 4K, 3D, and Full HD video, and can achieve maximum read speeds of up to 300 MB/s and maximum write speeds of up to 260 MB/s. Thanks to its U3 speed class rating, minimum write speeds are guaranteed not to drop below 30 MB/s.
UHS-II cards achieve their speed through an extra row of pins, and while this card has been designed for cameras that are UHS-II / U3 compatible, it may be used in devices that do not support UHS-II / U3. However, bear in mind that this card will then default to your device's speed class and bus rating, such as U1 and Class 10, each of which guarantee minimum write speeds of 10 MB/s.
As with most Lexar media, this memory card is able to withstand temperatures from -13 to 185°F, allowing you to take this card with you into extreme environments, such as snow and deserts. Should the card become compromised, it is protected by a limited lifetime warranty. Included is a UHS-II SD card reader, which will let you download material on this card using your system's USB Type-A port.
Please note, highest transfer speeds achieved only when paired with an SD UHS-II reader