The CH2 and CH3 buttons have slightly poor contact. There are scratches around the center two TRIM knobs (please check the second photo). Operation confirmed, with instruction manual. 【Multi-function DJ Mixer】 The Technics SH-MZ1200 is a 4-channel DJ mixer with microphone and digital inputs. It can connect to various sound sources, expanding the range of your performances. 【High-Quality Sound】 Trim and EQ controls are equipped on each channel, making sound quality adjustment easy. This allows for clear and professional sound. 【Effect Function】 It has an effect send function, and by connecting an external effect unit, further sound processing is possible. This allows you to create your own unique sound. - Brand: Technics - Model: SH-MZ1200 - Number of Channels: 4 channels - Microphone Input: 1 system - Digital Input: 1 system - Output Terminals: Master output, digital output - Effect Send: 1 system - Trim Control: Available on each channel - EQ Control: Available on each channel