The MC4 cable is UL listed as PV Cable.

100 Foot MC4 (Solarline 2), Extender Cable with one male and one female connector. Often used to connect panels that are spaced too far apart to use the built in cables on the solar panels. They are also used to bring the positive (+) and negative (-) ends of a string back to the combiner box.

#8 gauge (AWG) stranded copper (19 strand), single jacket wire
Outdoor rated insulation
UL listed