Want to save space on your mobile device by running apps from a memory card? Transcend's microSDXC/SDHC 300S cards are the right choice! Compliant with the latest speed class, the cards boast excellent random read/write speed, perfect for retrieving small pieces of data from random locations and speeding app launch time. It's common for users to install and run mobile apps from microSD cards in order to free device memory. Random read/write performance is thus crucial. Transcend's microSDXC/SDHC 300S memory cards are a great fit for storing mobile apps. The Application Performance Class was introduced to adapt this new trend. Transcend's microSDXC/SDHC 300S memory cards meet the new A1 standards, delivering minimum random read of 1,500 IOPS and random write of 500 IOPS, and sustained sequential speeds of at least 10MB/s. Transcend's microSDXC/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. In addition to excellent random read/write performance, Transcend's microSDXC/SDHC 300S memory cards come in up to 256GB storage capacity, allowing you to keep more digital files and apps at hand! To deliver the best performance and stability, Transcend's microSD memory cards are tested to withstand extreme conditions. They are temperature resistant, waterproof, shock proof, X-ray proof, and static proof.