Synology RX418 delivers an effortless solution for volume expansion and data backup for Synology 1U RackStation by adding 4 additional SATA drive bays on-the-fly. With its short-depth chassis design, RX418 ensures easy installation and deployment in 2-post racks and wall mount racks. Synology RX418 is backed with Synology's 3-year limited warranty. Models supported RS818+, RS818RP+, RS816, RS815+, RS815RP+, RS815. Synology Live Chat available - https://www.synology.com/en-global