Quality 12V Lithium Ion Battery Pack, 11.1V/9000Mah 99.9Wh Portable Power Bank,
Capacity: 11.1V/ 9000mAh 99.9Wh. Output: DC 12V/6A Max. TalentCell 9000mAh Power Bank. 9000mAh Portable Power Bank. But most guitar pedal input port is inner Negative(-), outer Positive(+). Input: 12V/6A(Max.).