A:Answer The detailed answer to this question is available on Tablo's web site. In brief: The QUAD does not have any built-in storage for recordings. You need to add a hard disk, either an external USB drive or an internal 2.5" SATA drive. The maximum capacity supported by the Tablo is 8TB, but height restrictions for an internal drive limits the maximum is 4TB when an internal drive is installed. Each 1TB is enough for 250-300 hours of recording storage. Personally, I use my Tablo QUAD mostly for time shifting, not for retaining many movies or full seasons of TV series. I use the 1TB internal SATA drive recommended by Tablo. It has plenty of storage for me.