An SD card is called a secure digital card for keeping memory. The mavic mini needs a SD card of UHS -I which has 30 MB/sec compose speed. There are various memory capacities of SD cards. Compose speed depends on data transfer. Fastest of data transfer, fast you will get pictures and videos. Any miniature SD card over this compose speed is excessive as you will not get the advantage of the quicker velocities in your recording. In the event that you need to guarantee quicker read speeds. Quicker read and write speed will give you fast tasking. Mavic Mini likes the Sandisk Extreme Plus and Extreme Pro arrangement of memory cards.