As is per usual for Supermicro, there are multiple model numbers/SKUs that refer to the same chassis. The chassis itself, independant of the installed SAS expanders, seems to be called the sc847j. The product name / model number SC847E16-RJBOD1 seems to refer to the 45 disk bay version of the sc847 (sc847j) with the dual link SAS expanders installed (E26 vs E16 in the model number). To complicate things further, even though the model number specifies an exact combination of parts, it’s not an orderable SKU. The orderable part number is CSE-847E26-RJBOD1.