The HP ProBook 430 G4 Notebook Comes in Different Storage Configurations and Supports Either 1 or 2 Drives Depending on the System Board Installed. (Single and Dual Drive Options with a 7th Gen Intel Core i3/i5/i7 Processor: One 2.5" Drive and/or One M.2 NGFF (2280) Solid State Drive) or (Single Drive Options with a Intel Pentium 4415U or Celeron 3865U Processor: One 2.5" Drive or One M.2 NGFF (2280) SATA Solid State Drive using a M.2 Drive Bracket) Note: When the M.2 (2280) Drive is installed in models with a Intel Pentium or Celeron Processor, the M.2 Drive occupies the 2.5" Drive bay by using a M.2 Drive bracket p/n 911705-001. If replacing the M.2 Drive for a 2.5" Drive in models with a Intel Pentium or Celeron Processor, or adding a 2.5" Drive to models with a 7th Gen Intel Core i3/i5/i7 Processor, you will need the 2.5" Drive cover p/n 905736-001 for installation. (The M.2 Drive board and the M.2 slot support SATA only Solid State Drives)