Synology RX415 Published October 8, 2014 at 1024 × 1024 in Synology Expansion Unit RX415 4-Bay 3.5″ Diskless NAS (1U Rack) for Scalable Models (SMB) Synology Expansion Unit RX415 4-Bay 3.5″ Diskless NAS (1U Rack) for Scalable Models (SMB)