What makes N2R1D so unique is that it has a built-in DVD burner which serves as an additional back up option where you can store up to 4.7GB on to a single layer DVD disc or up to 8.5GB on a dual layer disc. This is great because you can quickly copy important data to a DVD discs if you need them on the go or if you want to store important data and store somewhere for a safe keeping. As an added feature, LG NAS also has a built-in four-in-one memory card reader, three USB ports, and eSATA port for adding additional storage devices or connecting mobile devices such as external hard drives and MP3 players. For better Raid Management, LG NAS also offers Selective Mirroring function which allows users to back up selected folders. With this function, it will allow users to increase NAS efficiency and storage capacity.