A resonator ukulele or "resophonic ukulele" is a ukulele whose sound is produced by one or more spun aluminum cones (resonators) instead of the wooden soundboard (ukulele top/face). These instruments are sometimes referred to as "Dobro ukuleles," however the term "Dobro" is currently trademarked by the Gibson Guitar Corporation. Though resonator guitars are often played flat in the lap steel guitar style, resonator ukuleles are almost exclusively played in the conventional manner.