Shipment arrived quickly. Card inserted in my new Panasonic HC-V757EG-K camcorder and formatted. When recording, there was often crashes the camcorder, it could no longer be off just picking up the Batteries ended this condition. I then resorted yet deeper into their pockets and looked at the SanDisk SDSDXPA-064G-X46 Extreme Pro SDXC 64GB bought the runs without problems. Even my older Transcend Extreme Speed SDHC 32GB Class 10 runs without problems.