SanDisk Extreme 64 GB microSDXC Memory Card + SD Adapter. Up to 90 MB/s, Class 10, UHS Speed Class 3 (U3), UHS Video Speed Class 30 (V30). Also temperature and water proof. I'm aware you can get slightly cheaper alternatives but this is a decent price for what is a quite significantly faster card. For applications like shooting 4k videos the extra couple of quid is definitely worthwhile for the U3 rating. Selling for 23.99 at Argos and 24.99 on my memory, This is the Cheapest its been on Amazon, I asked the three camels and they told me.