SanDisk 8GB  Ultra microSDXC UHS-I Memory Card Full HD Micro SD Card
 
About speed:
How to verify the Capacity and Speed of the memory card?
①. Please use quality USB 3.0 card reader to verify all memory card by H2testw on PC. Real memory card should pass H2testw with no error.
②. Please don't use cheap card reader to test Micro SD card, speed of Micro SD card will be reduced by low quality card reader.
③. Micro SD memory card speed is greatly affected by card reader and the capacity you choose , USB port ect. Low quality device will 100% slow down card speed.