From the manufacturer:
”Looking for a string that sounds super good and plays super good? Then you need to check out our Super Light Naturals.
With this set, you really get the best of both worlds, because they’re perfect for players who are looking for a flexible, but still full-sounding string. This has to do with alloy used in our Naturals, which gives these strings a warmer sound that’s normally associated with a heavier gauge string.
Naturals are our take on Phosphor Bronze, which is great at bringing out the the authentic, woody characteristics of an acoustic guitar. It’s this rich copper alloy that gives these strings a distinctly warm, resonant tone. The strings also have a rose gold color so beautiful you’ll want to order an extra set just to frame and hang on the wall.
As an added bonus, component agents in this alloy make these strings especially resistant to corrosion, meaning your strings will sound better, longer. Who wouldn’t like that?”