Amazon.com: D'Addario EXP17 Coated Phosphor Bronze Acoustic Guitar Strings, Light, 13-56 – Offers a Warm, Bright and Well-Balanced Acoustic Tone and 4x Longer Life - With NY Steel for Strength and Pitch
Phosphor Bronze vs 80/20 Guitar Strings: Which is Right for You?
Authentic Acoustic SP® Guitar Strings Phosphor Bronze | Martin Guitar