Mac Pro supports up to four 3Gb/s Serial ATA hard drives for up to 3TB of storage. The cable-free, direct-attach drive solution lets you install and remove drives in a snap. To install a drive, you connect a simple drive carrier to the hard drive, then just slide it into place - no cables or connectors to hassle with. Removing the drive is just as easy. Every Mac Pro ships with four hard drive carriers. This solution is perfect if you ever share drives among different workstations at home or the studio.