Aria Pro II electric guitar strings are made from nickel plated steel wire wrapped around a hexagonal core. Light Gauge E-1st .010 Plain Steel B-2nd .013 Plain Steel G-3rd .017 Plain Steel D-4th .026 Nickel Plated Round Wound A-5th .036 Nickel Plated Round Wound E-6th .046 Nickel Plated Round Wound