Description: Caddy Height/Thickness: 12.7mm. Caddy Interface for hard drive: SATA. Caddy Interface for motherboard: SATA. The Caddy/Adapter for a second hard drive in your optical bay offers you new maximum data storage flexibility. With the second HDD/SSD in your laptop, you can replace the optical drive and quickly back up important applications and critical data. Simply remove the CD-ROM drive and insert the Caddy (with the added hard drive) in its place. The built-in locking screws facilitate the installation of the second hard drive into the caddy. The caddy is made of aluminum, which makes it lightweight, durable, and provides cooling for the hard drive. Internally, the caddy features a plastic support that absorbs noise and vibrations from a second HDD/SSD. An updated SATA board is included to correct shutdown issues with a second HDD/SSD. Third-party replacement part. Detailed features: Plug & Play. Fast and reliable connection like with the main HDD.