The new 4GB SD High Capacity (SDHC) cards are based on the SD Association 2.0 specification and tested to be fully compliant with SDHC host devices.
The SDHC form factor addresses the growing usage of larger capacities supported by high performance digital cameras, digital camcorders and other handheld devices used to record high definition digital content. While the maximum capacity for a standard SD card is capped at 2GB, the new SDHC standard extends storage capacity from 4GB to 32GB. Identical in size to todays standard SD cards, SDHC cards will work only with SDHC compatible host devices. End consumers are encouraged to look for the SDHC logo to ensure compatibility. Manufacturers currently offering SDHC compatible devices include Canon, Nikon, Panasonic, Casio, Pentax, Sanyo and Palm, with available host devices ranging from digital camera, digital camcorders to smart phones. In Corsair lab tests, a 4GB SDHC card can store up to 19 hours of high definition MPEG 4 movies or 1000 MP3 songs. The new SDHC standard brings a unified speed rating system defined by the SD Association, where three speed classes (Class 2, 4 and 6) bring guaranteed minimum sustained transfer rates for optimal performance.