Electric Guitar Nickel (100% Nickel) Nickel (100% Nickel) *Round Core Rock Formula (Alloy 52) Steel (8% Nickel Plated Steel) 7-String Acoustic Guitar Phosphor Bronze Phosphor Bronze *Round Core Lost '60s Acoustic (Bronze 85) Blue Grass and Other Banjo Mandolin String Gauge 8's Eights 9's Nines 9.5's Half Gauges 10's Tens Perfect Tens 11's Elevens 12's Twelves 13's Thirteens String Core Hex Core Round Core Accessories & Merch Apparel Picks Decals