Powerful and scalable 4bay NAS for growing businesses, 4 x Drive bays for 3.5" SATA HDD/2.5" SATA HDD/SSD, 2 x M.2 NVMe 2280 SSD slots, AMD Ryzen R1600, 4GB DDR4 (upgradeable to 32GB 2x 16GB), 2 x USB 3.2, 2 x Gigabit Ethernet. Compatible RAM Model D4ES024G (DDR4 nonECC SODIMM) Expansion Unit Available DX517 (5 Additional Bays)