Amazon.com: Micro Center 256GB Class 10 MicroSDXC Flash Memory Card with Adapter for Mobile Device Storage Phone, Tablet, Drone & Full HD Video Recording - 80MB/s UHS-I, C10, U1 (1 Pack) :
SanDisk 256GB Ultra microSDXC A1 UHS-I/U1 Class 10 Memory Card for Chromebook, Speed Up to 120MB/s (SDSQUA4-256G-GN6FA) - Newegg.com
SanDisk 256GB Extreme PRO SDXC Class 10 USH-3 V30 Flash Memory Card - Micro Center