Aquila 85U RED SERIES, Ukulele CONCERT Regular Tuning, Key of C - GCEA ressing strongly the string on the frets, the note does not became sharper.It is not necessary to file the nut slot wider to accommodate it. set / Concert Ukulele g' c' e' a' - Regular Tuning, Key of CMade of a mixture of NYLGUT andred copper powderColour: red-brownRed Series - Nylgut made firstly elastic and then added with red copper powder in order to increase the density to about twice that of standard white Nylgut.Slightly rough surface; this texture has eliminated the squeak that sometime happen with the Nylguts.The new red-brown strings feature a great feel, excellent elasticity andaccurate intonationpast the 12th fret.P