The Lenovo B330-15IKBR Laptop Supports Single and Dual Drive Configurations. (One 2.5" Solid State Drive or Hard Drive in Internal Primary Bay and One 2.5" Solid State Drive or Hard Drive in Optical Drive Bay) Note: The second 2.5" Drive replaces the optical drive when Installed. If installing the second 2.5" Drive in replace of the optical drive, you will need additional parts for installation.