Ernie Ball Cobalt Slinky Electric Bass Guitar Strings provide an extended dynamic range, incredible harmonic response, increased low end, and crisp, clear highs. Cobalt provides a stronger magnetic relationship between pickups and strings than any other alloy previously available. Cobalt Slinky bass guitar strings are also soft and silky to the touch, making string bending a breeze. Gauges .050, .070, .085, .107