In the DR tradition of using old-style construction to improve modern performance, Pure Blues Big N' Heavy electric guitar strings are designed with pure nickel wrap wire, round wound on round cores. While this is a slow, expensive method of string making, it does produce a string acclaimed for increased sustain, vintage tone and great low tones for playing rhythm to lead. The extra step of winding pure nickel around a round core gives the Pure Blues a punch that players say they are surprised to get in a vintage style string.