UK-1 makes it simple to reproduce the authentic sound of your uke without modification. Simply slide the UK-1 onto the tie block and retighten the strings. UK-1 fits most soprano, concert, tenor and baritone ukuleles with a tie block. This passive piezo system is designed to work flawlessly with your favorite acoustic amplifier or colored via your preamp of preference. 1/8" to 1/4" cable included.