JCraft Medium Custom 5-String Electric Bass Guitar String 45-130JCraft Bass Strings are built in special gauges to deliver the right tension for the discerning bassist. They are made with the timeless combination of hexagonal core wrapped in nickel alloy for the best tone and durability. The medium custom has a slightly thicker low B string for a tighter tension 1st String: 0. 045 2nd String: 0. 065 3rd String: 0. 085 4th String: 0. 105 5th String: 0. 130 For heavy gauges, try the JCraft X Heavy Core Electric Bass