A professional-grade CFexpress Type B cardcapable of maintaining a 1700MB/s sustained sequential write speed. ProMaster Velocity Cine CFexpress Type B Memory Cards achieve breakneck speeds. With a 1700MB/s minimum sustained sequential write speed, this 150GB card can handle the most rigorous use in professional applications. In addition, this durable card is weather-resistant, shock-proof, magnet-proof, static-proof, and X-ray-proof. This card is backed by a 48-hour replacement guarantee and a limited lifetime warranty.