This is the Boss multi-function graphic equalizer, the EQ-20. Unusually for a graphic equalizer, it can store settings. You can switch between manual and memory modes, allowing for both correction and boosting with a single unit. Operation has been confirmed with no particular issues. It is a used item, so there are some minor scratches, but it is still usable. I am selling it because I purchased a different equalizer. Please understand that this is a used item and that it is sold as-is, with no returns. - Model: EQ-20 - Type: Graphic Equalizer - Connections: INPUT, OUTPUT - Level Adjustment: LEVEL adjustment function - Power: DC 9V adapter Thank you for looking. #boss #equalizer #eq-20