GHS Coated Boomers Custom Light. Each set includes six strings of gauges 9-46. For over forty years, Boomers have been known as "The Power String", and continue to be the standard for musicians in many genres. Known for their bright characteristic, long-lasting tone and powerful attack, Boomers are the ideal nickel-plated steel string for all of your musical needs. Coated Boomers have outstanding extended performance life and powerful tone.