Musiclily Alice Nickel Wound 4-String Acoustic Bass Guitar Strings Set, Regular Light 100% New,Fit for regular size of 4 string acoustic bass greatly he Guitar Strings are in the material as follows: 4 strings in Steel Core with Coated Copper Alloy Wound Specifications:G string -1st Steel Core, Coated Copper Alloy Wound .040" 1.02mm;D string -2nd Steel Core, Coated Copper Alloy Wound .060" 1.52mm;A string -3rd Steel Core, Coated Copper Alloy Wound .075" 1.91mm;E string -4th Steel Core, Coated Copper Alloy Wound .095" 2.41mm the package is like the pictures showed Package Include: 1 set Bass Strings Set