Behringer UO100 Ultra Octaver.
Create monster sound by adding two additional tones using your guitar?one and two octaves below the original tone. This BEHRINGER product has been designed to compete head to head with leading products on the market. There are dedicated volume controls for all three tones for effective sound shaping, and a flexible 3-mode Range switch allows ultimate bass performance. We?ve included a status LED for effect On/Off and battery check, and you can run your UO100 on a 9 V battery or a DC power supply (not included). For absolutely noise-free operation, a first-class electronic On/Off switch is integrated. The UO100 works wonderfully with bass too!

Designed for use with: Guitar/Bass