4 bay nas nas enclosure max hard drives 4 hard drive form factors 25 35 inch hard drive types hdd ssd hard drive mounting removable drive hard drive access top hard drive location horizontal internal interface sata iii target audiences home users small and medium sized businesses smbs internal file system ext4 external file systems ext3 ext4 ntfs fat32 hfs raid levels 0 1 5 6 10 5hot spare jbod connections 3x usb 30 1x usb 20 2x rj 45