You can easily upgrade the HDD, RAM memory and DVD-drive of the Asus N552. The factory hard drive (or SSD) and RAM memory is hidden behind a removable compartment cover. The compartment cover can be found at the bottom of the notebook. It is secure with only 2 screws. Remove these screws and you’ll notice the HDD Bay and RAM memory. The factory HDD or SSD is covered with a HDD Bracket. This bracket is transferable to any 2.5 inch SATA SSD or HDD. You can also easily upgrade the RAM memory or add another RAM memory in the 2nd slot. The DVD-drive is only secure with one screw. You can find this screw in the middle of the bottom cover. Once the screw is removed you can easily slide out the DVD-drive. The metal bracket and bezel can be easily transferred to the HDD Caddy. Also the HDD Caddy should easily slide back in the DVD-bay.
For the Asus N552 HDD Caddy you can find this model here: