Seagate manufactures hard drives that specifically address the demand for hyperscale cloud scalability. As the flagship of the Seagate® X class, the Exos® X18 enterprise hard drives are the highest-capacity hard drives in the fleet. Exos X Series Hard Drives The most scalable drives in the datasphere, Exos X series hard drives integrate the latest technology in support of a secure and reliable cloud data center. Exos X18 Designed for maximum storage capacity and the highest rack-space efficiency, delivering up to 18TB capacity.