Martin Phosphor Bronze Acoustic Guitar Light Gauge Strings.
Phosphor Bronze Wound. Composition is 92% Copper, approx 8% Tin and a small amount of phosphorus - producing a warmer tone compared to 80/20 Bronze (which is actually 80% copper and 20% zinc ie technically Brass, not Bronze!!)
0.012
0.016
0.025
0.032
0.042
0.054