This product is either discontinued or we cannot get that from suppliers.
Synology RackStation RS820RP+ 4-Bay 1U Diskless Scalable NAS with Redundant PSU, Intel Atom C3538 4-Core Up to 2.10GHz, 2GB DDR4 (Expandable up to 16GB), 4x 2.5"/3.5" SATA HDD/SSD Bays, 2x 40mm System Fans, 4x RJ-45 1GbE LAN Port, 2x USB 3.0, 1x eSATA Port, 1x PCIe Gen3 x8 Slot (x4 Link), 150W Redundant PSU, 1U.
Synology RackStation RS820+/RS820RP+ is designed for businesses pursuing an effective and centralized data management. It comes with four drive trays and 1GbE LAN ports and supports an optional 10GbE network or M.2 SSD adapter card.