Ernie Ball Slinky 6-String w/ Small Ball End 29 5/8 Scale Bass Guitar Strings, 20-90 GaugeErnie Ball Nickel Wound 6 string Electric Bass Strings are made from nickel plated steel wrapped around a hex shaped steel core wire. Each 6 string bass guitar string produces a bright, balanced tone and manufactured with small ball ends like guitar strings, not large ball ends used on traditional electric bass stings. Gauges . 020, . 030, . 042, . 054, . 074, . 090