uhs speed class 3 card

UHS Speed Class 3 (U3) guarantees a minimum sustained write speed of 30 MB/s.

Video Speed Class V30 guarantees a minimum sustained video write speed of 30 MB/s.

Reported read speeds range from about 90 MB/s up to roughly 200 MB/s. Reported write speeds fall roughly between 45 MB/s and 90 MB/s. All of these cards meet the U3/V30 minimum sustained write requirement of 30 MB/s.

When used in devices that don’t support UHS-I, U3 or V30, the cards will fall back to the device’s supported speed class or bus rating (for example UHS-I U1 or Class 10). In those cases the device’s guaranteed minimum write speed may be lower (for example around 10 MB/s for Class 10/U1).

These cards are marketed for UHS-I devices such as digital cameras, DSLRs, camcorders, action cameras, and mobile devices.

Descriptions commonly list support for 4K (4K UHD) and Full HD video recording; one listing also mentions 3D video capture.

Common durability claims include waterproofing, shockproofing, X-ray protection, resistance to static and vibration, and a wide operating temperature range (example range cited: −13 to 185°F).

The listings show both SD and microSD form factors, with capacities including 128 GB, 64 GB, and 32 GB.

Some SD cards include a write-protect switch, and many microSD cards are sold with an SD adapter.

High-performance listings advertise offload/read speeds up to about 180–200 MB/s and write speeds up to about 90 MB/s.