Please check below maximum supported external storage size info.
There is NO physical limit, just there is partition and format file system limitation.
Please make (1x) full partition and format USB to NTFS type as follows: HOW TO FORMAT
256GB (Gigabytes) is the maximum supported size on Formuler Android-based products.
IF this doesn't answer your doubts or you want to search more information,
Please take a look at threads in our forum FORMULER FORUM Or click TAGS on the right side of this page.