Compressor/limiter with three adjustment knobs. - Model Name: CL9 - Type: Compressor/Limiter - Brand: behringer - Input/Output Terminals: IN/OUT terminals - Control Knobs: 3 adjustment knobs (AT, TIME, SUSTAIN) Operation confirmed. No box. Returns are not accepted due to the possibility of product substitution. The Velcro attached to the back can be removed. Thank you for viewing.