Designed to record for up to 20,000 hours(1), the SanDisk High Endurance microSD card gives you the peace of mind that your dash cam, home monitoring or security system will capture crucial footage when it happens, recording and re-recording worry-free. It?s built tough too-ready to record in extreme heat or freezing cold, and it?s shockproof, waterproof and x-ray proof.(2) It?s also rated Class 10, U3 and V30(4) so it has the speed you need to record in Full HD or 4K.(3) Capacities of up to 256GB* let you record and save more video, and read speeds of up to 100MB/s(5) let you transfer that footage fast. | *1GB = 1,000,000,000 bytes. Actual user storage less. | (1) Actual hours of video saved less. Up to 20,000 hours for 256GB; 10,000 hours for 128GB; 5,000 hours for 64GB; and 2,500 hours for 32GB. Full HD video only; total hours less for 4K UHD video. | (2) Card only. See product packaging for more information and limitations. | (3) Compatible device required. full HD (1920x1080) and/or 4K UHD (3840x2160) video support may vary based on host device, file attributes, usage conditions and other factors. See official SanDisk website for more details. | (4) UHS Speed Class 3 (U3) and UHS speed class 1 (U1) designate performance options designed to support real-time video recording with UHS-enabled host devices. Video speed class 30 (V30), sustained video capture rate of 30MB/s, designates a performance option designed to support real-time video recording with UHS-enabled host devices.