From Ernie ball site: "

Ernie Ball Cobalt Slinky Electric 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. " 

Gauges: 12-56

This set is a pretty hefty set of strings, works awesome for down tuning, unless you've got some beastly hands don't expect much bending on these bad boys!

If you have any question regarding these strings and if they are suitable for your particular instrument, shoot a message and we will be happy to answer any questions you may have.