Set of strings designed for 4 string bass. Pitbull has developed high quality strings using the finest American steel wire. Pitbull produced the Gold Series with the material sounding the best. With Pitbull's technology background, the Gold series has an excellent balance of tension and tone with maximum sustainability. Longer-lasting PITBULL GOLD series bass guitar strings are ideal for bass guitarists who want a deeper, sustainable bass sound. The best American-made steel core is wrapped with the best quality nickel alloy steel wire. Strings are suitable for long scale bass. Light, Thickness: 045w, .065w, .080w, .100w