Ukulele Amplifier UKULELE AMP 3W Electric Ukulele Speaker-4 String Guitar AMP Output power: 3 Watt. Speaker: 3 inch, 4 ohm. Dimensions: 123 (W) x 125 (H) x 60 (D) mm. Weight: 529g (Not Including Battery 9V 6F22). Volume Control: Setting volume from low to high, Tone Control: Bass to Treble tone control, AUX IN: Connect to audio device, such as any MP3 or even your iPod. Phones: Output for stereo earphones (once you connect it to earphone, it will automatically disconnect the speaker). Input: Connection for musical instrument DC Jack: Connection for AC adaptor (not included), 9V 500mA (min) Best mini amp for your ukulele , guitar , violin and especially for ukulele