This is a CFexpress B memory card with a capacity of 512GB and a read speed of 1950MB/s. I purchased it, but it turned out to be incompatible with my camera, so it's an unused item that has only been opened once. - Brand: Nextorage - Model Name: B2 SE - Capacity: 512GB - Read Speed: 1950MB/s - Write Speed: 1900MB/s - Standard: CFexpress B Thank you for looking.