Pure Nickel wound strings were used exclusively on most guitars built in Fiftys and most of the Sixtys. Pure Nickel has a slightly warmer tone than nickel-plated steel and is preferred by many blues artists.
Pure Nickel Wound strings are created by wrapping Pure Nickel alloys around a hex-shaped core wire which is made from tin-plated high-carbon steel (same as plain strings, but hex-shaped).
These strings performed excellent. They do not break easy, stay in tune better, and last longer than regular more inexpensive strings. I used them on a long scale guitar tuned to Eb and found them to be a better balanced set and felt closer to a normal 10-46 set while in the flat tuning. Shipping was efficient as well.
I gave the strings a 4 because I reserve the best place to Matt Schofield's signature set! However, these strings are great sounds with nice highs and a tight bottom. IF you like that "Jingle-Jangle" snappy tone for a strat, these are just perfect. Also, like all of Curt's strings they stay in tune and do not break easily. I've never broken one of curt's strings and I bend the heck out of them! I always feel confident that his strings will not break and that helps me to play my best in live performances. Tone, Tone, Tone!