Class A guitar effects router with phase inversion function. - Brand: Radial - Model Name: EXTC-SA Effects Reamper - Function: Class A guitar effects router - Adjustment Knobs: SEND, RECEIVE, BLEND - Features: Phase inversion function - Patent Number: US Patent #6,005,950 Thank you for viewing. I am selling this item to organize my equipment. I purchased it used. I haven't used it for several months, but during a recent operation check, FX loop A had some crackling. Loop B was problem-free. The box and manual are not included (operation instructions are available online from the official website). AC adapter is included. Thank you.