Elixir acoustic guitar strings. Phosphor bronze. They're expensive, but they're good strings that last longer than the price suggests. ELIXIR NANOWEB Phosphor Bronze CUSTOM LIGHT I bought a bonus pack [3 sets in a box], but I only used one set, so this is for the remaining [2 sets]. I bought them recently, but I won't be changing strings again for a while, so I'm putting them up for sale. Please check the gauge of each string in the photos. It seems that the bonus packs themselves are in short supply this year. I am also selling on other flea market apps, so I may have to cancel your purchase. In that case, I will give priority to the person who purchased first. Thank you for your understanding. Below is the manufacturer's website description. Phosphor Bronze NANOWEB® coating maintains the brilliance and rich tone unique to phosphor bronze strings for a long time. No. 1* acoustic guitar strings in the United States The only coating technology that completely covers the wound strings prevents dirt from entering the gaps in the windings. Higher sound quality and longer life compared to other coated/non-coated strings You can play whenever you want Improved playability with a smooth feel Reduced finger noise, perfect for both live performances and recordings Anti-Rust plain strings with corrosion-resistant processing are used to achieve long life for all strings in a set. Reduces the frequency of string changes, allowing you to focus on playing.