The Lenovo ThinkPad T440p Laptop Supports up to 3 Drives. (One 2.5" Solid State Drive or Hard Drive in the Primary Drive Bay and One M.2 (2242) Solid State Drive for Caching and One 2.5" Solid State Drive or Hard Drive in the Optical Ultrabay Slim) 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 the slim ultrabay for installation.