From the StringJoy site: 

SUPER LIGHT Gauges: .011 – .015 – .022w – .030 – .040 – .052

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?

LIGHT Gauges: .012 – .016 – .024w – .032 – .042 – .054

Looking for a set of acoustic strings that have just the right amount of tension, the right amount of tone, and still have enough volume to annoy your neighbors? Then you need a set of our Light Naturals.

These are going to work great for most guitarists, since they provide excellent low-end and midrange volume while still being easy on those calluses.

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?

MEDIUM Gauges: .013 – .017 – .025w – .034 – .044 – .056

Our Medium gauge set is the go-to string for players who want a big, warm, beefy tone out of their guitar that will project with plenty of volume and definition. Pair that with the powerful low end of our Naturals, and you’ve basically wrapped yourself up in a blanket of tone so warm you could sleep outside in the Alaskan wilderness in the middle of winter. Take that hypothermia!

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?