Update to the update ISX 600 alternator belt. Belt is Cummins 5VX680, but there is a quirk!

. I ordered and received a 5VX680 Cummins belt, but when my service people pulled the belts to replace them, the 5VX680 on the engine is a double belt made as a single belt. The 5VX680 I just received is a single 5/8” belt. Both belts are clearly labeled 5V680 but they are NOT the same belts!
More mysteries from Cummins!