SanDisk Extreme Pro 512GB microSDXC UHS-I V30 200MB/s Read 140MB/s Write Memory Card for 4K Video on Smartphones Action Cams & Drones: Improve your workflow efficiencyWith SanDisk QuickFlow Technology, this card optimizes performance for timesaving media offloads with quick read speeds up to 200MB/s (64GB - 1TB). Pair with the SanDisk Professional PRO-READER SD and microSD to achieve maximum speeds (sold separately).Write speeds of