Read Speed: SanDisk 512GB Extreme PRO microSD UHS-I Card features SanDisk QuickFlow Technology that optimizes performance for timesaving media offloads with quick read speeds up to 200MB/s Write Speeds of up to 140MB/s: Capture fast-action photos or shoot 4K UHD video with write speeds of up to 140MB/s. The SanDisk Extreme Pro microSDXC UHS-I Card lets you shoot more and faster Load Apps Faster with A2: Get faster app performance for an outstanding smartphone experience thanks to the SanDisk Extreme Pro microSD card’s A2 Specification Durable Design: This card is shockproof, temperature-proof, waterproof, and X-ray-proof, so you can enjoy your adventures without worrying about the durability of your memory card Ideal For: This card is ideal for recording outdoor adventures, weekend trips, or sporting events without skipping frames