SMB 4-Bay NAS QTS/QuTS hero OS, Intel Core i5 Processor, 4GB DDR4 RAM(1 x 4 GB) max 64GB RAM (2 x 32 GB), 4 x 2.5/3.5" SATA HDD + 2x M.2 PCIe SSD slot, 2xGbE LAN, 1 x 10GBase-T, 2 x Thunderbolt 3 port