Transcend's SDXC/SDHC 300S memory cards meet both the UHS Speed Class 3 (U3) and the UHS Video Speed Class 30 (V30) standards for 4K Ultra HD video recordings, with read/write speeds of up to 95MB/s and 45MB/s respectively. * U3 and V30 compliance applies only to 64GB-480GB capacity cards. With up to 480GB storage capacity, Transcend's SDXC/SDHC 300S memory cards allow for thousands of photos and hours of Full HD videos to be recorded, meaning you can stay focused on capturing fantastic moments without worrying about running out of storage. To deliver the best performance and stability, Transcend's SD memory cards are tested to withstand extreme conditions. They are temperature resistant, waterproof, shock proof, X-ray proof, and static proof. Transcend offers RecoveRx software, a data recovery utility that allows you to search deep within a storage device for traces of erased files including digital photos, documents, music and videos. UHS-I provides faster bus speed using just one row of pins, while UHS-II uses two lanes for even faster data transfer via two rows of pins. The symbol "I" means UHS-I, and "II" means UHS-II. Please make sure your device supports the same standard to benefit from the increased speeds. Speed Class defined by the SD Association includes Class 2, 4, 6 and 10. Each class is defined for a minimum sequential write speed. For example, Class 10 guarantees a minimum data transfer rates of 10MB/s. UHS Speed Class includes UHS Speed Class 1 (U1) and UHS Speed Class 3 (U3). UHS Speed Class 1 supports a minimum 10MB/s write speed, whereas UHS Speed Class 3 supports at least 30MB/s write speed. Video Speed Class is defined to answer a demand for high resolution and high quality 4K8K video recording. V60 (60 MB/s) and V90 (90 MB/s) can support 8K resolution, while V6, V10 and V30 capture high-definition and 4K resolution and guarantee minimum sequential write speeds of 6 MB/s, 10 MB/s and 30 MB/s respectively.