for Dell Chromebook 3100 USB IO Board 30-pin Ribbon Cable- genuine Dell OEM Ribbon Cable that connects the tight side USB IO board to the motherboard; 
for the 3100 2-in-1 and 3100 LAPTOP systems that do NOT have the optional LTE 4G WWAN wireless. There are two cables that connect the IO board, this is the 30-pin cable.

for Dell Laptops,Chromebook 3100 2-in-1,Chromebook 3100 Laptop WITHOUT WWAN.

DP/N: D2D9P, 0D2D9P

Alternate P/N's:
EDB10_IO_30P_FFC
NBX0002FQ00

NOTE: This cable will is NOT compatible with 3100 systems that have the optional LTE 4G WWAN wireless.