For all Macbook Pro Unibody 13″ 15″ 17″ you can use a HDD Caddy to replace the superdrive for a second hard drive. For the Macbook Pro Unibody we have specific designed HDD Caddy which is made of aluminum and the inside of the caddy has a plastic holder and its “hollow frame” design minimize noise and vibrations from a 2nd HDD. This HDD Caddy is also extremely light so the extra weight of a second hard drive is minimized. It will fit any 2.5″ HDD or SSD. The caddy supports SATAI, SATAII, and SATAIII transfer speeds. The built-in lock screws make it easy to mount your second hard drive in the caddy. A mini hexkey is included.