Pitbull Mutant series bass guitar strings are designed specifically for basses requiring multiscale or long length strings. They provide an excellent fit, particularly for basses requiring a 37'' length. They are composed of the highest quality nickel alloy windings wounded around a high-carbon alloy steel core. The tension has been specifically balanced for basses requiring extra length. They offer impeccable tuning stability and a smooth playing experience. Pitbull Mutant series bass guitar strings are made using the most advanced computer-controlled technology known to the world.