Used a few times after purchase and stored at home. Operation has been confirmed with the AC adapter and microphone connected. There are a few signs of use. ↓ From the sales site below Specifications ■ Stereo Mobile Amplifier ■ Output: 2.5W x 2 ■ Speakers: 4" x 2 ■ Connections ■ Included: Strap, Instruction Manual 【Microphone Channel】Input Jack (Standard Type) 【Keyboard/Instrument/Guitar】Input Jack L (GUITAR) / R (Standard Type) 【AUX In】Stereo AUX In Jack (Stereo Mini Type, RCA Pin) ■ Power: DC9V: 6 x AA batteries or AC adapter ■ Current Consumption: 175mA (DC9V) ■ Dimensions, Weight: 28W x 10.8D x 17.7Hcm, 2.4kg