To test, I have one panel connected at a time to the Charge Controller.
Both are 12V 100W panels, both with the same model number: RS-M100
The older one:
18.2V Vmp
5.49A Imp
22.1 Voc
5.96A Isc
10A Fuse rating
1.2" taller...other than that, same dimensions
The newer one:
18.6V Vmp
5.38A Imp...