The Acer TravelMate B3 B311RA-31 Laptop Comes in 2 Different Drive Options from Acer and Supports Single Drive Configuration Only. (One M.2 NGFF (2280) Solid State Drive) or (One eMMC Flash Drive) Note: the eMMC Flash Drive is integrated on the system board and is not upgradable. The M.2 NGFF (2280) Solid State Drive is upgradable. Please verify what your model supports before ordering.