SanDisk SDSDQXCZ-256G 256GB Extreme Pro MicroSD Card

The SanDisk Extreme Pro SDSDQXCZ-256G is a 256GB microSDXC card rated at up to 170MB/s sequential read and 90MB/s sequential write, with speed class certifications of UHS-I U3, V30, Class 10, and A2. These four ratings are not marketing overlap — each addresses a different performance floor. U3 and V30 together guarantee a minimum 30MB/s sustained write speed for continuous video recording. A2 certification specifies minimum 4000/2000 IOPS random read/write performance, enabling the card to function as Android app storage without the I/O bottleneck that slower cards create. At 170MB/s read, transferring the card's full 256GB capacity to a computer via a USB 3.0 reader takes roughly 25–30 minutes at peak speed — a meaningful improvement over mid-range microSD cards in the 80–100MB/s class.

SanDisk's four-axis durability rating — temperature-proof, waterproof, shockproof, X-ray proof — makes this card suitable for deployment in action cameras, drones, and rugged smartphone setups where consumer-grade storage fails under environmental stress. The card is specifically validated for Insta360 cameras and action camera platforms from other manufacturers that impose sustained high-bitrate write loads across multiple recording sessions. This bundle pairs the card with an Everything But Stromboli microSD reader and includes an SD adapter for standard slot use. The 256GB capacity provides a practical recording buffer for extended shoots — roughly 60–90 minutes of 4K video on most action cameras — reducing the logistical overhead of carrying and managing multiple smaller cards in the field.