The HP ProBook 470 G2 Notebook Supports Single or Dual Drive Configurations Depending on if the WWAN Card is installed. Dual Drive Options with no WWAN Card Installed: (One 2.5" Solid State Drive/Hard Drive and/or One M.2 NGFF (2242) Solid State Drive in the empty WWAN Slot) Single Drive Configuration with the WWAN Card Installed: (One 2.5" Solid State Drive/Hard Drive) Note: If the 2.5" Drive was not installed from HP, you will need the 2.5" Drive hardware kit p/n 767437-001 (Includes: 2.5" Drive bracket and screws) for installation.