This string set has a "low G" string, meaning that the typical G string is tuned an octave lower and is a steel wound Nylgut core string. This extends the low register of the ukulele by a fourth and is a fun option that can definitely open some creative doors! Everybody seems to be familiar with these strings! They are probably the cheapest "upgrade" to any ukulele that is slightly lacking in sound, volume, and tone. Its no coincidence that these strings come "stock" on most production model instruments these days. Aquila strings definately do a lot boost the sonic characteristics of most ukes out there. Aquila "Nylgut" technology is an attempt to retain the sonorous and appealing tone of "gut" style strings without the negative qualities such as temperature and humidity sensativity and over-all grossness. I must say they have been wildly successful in this endeavor! Grab a set and see the results yourself!