Feature:1. Passive Preamp/Speaker Volume Controller: It needs no external power supply to work--plug and play.2. Small Body: Ultra-compact controller, made of solid durable metal housing, is space-saving, easy to carry.3. High Sound Quality: Stable, lossless transmission ensures pure, sound with no noise.4. Easy Control: Front panel has switch to select fully-balanced or single-ended input/output; back has RCA \u0026 XLR interface.5. Wide Application: The device can connect with audio equipment that has no volume adjustment, very suitable for stereo system.Specification:Features:Passive Preamp/Speaker Volume Controller:It needs no external power supply to work--plug and play.Small Body:Ultra-compact controller, made of solid durable metal housing, is space-saving, easy to carry.High Sound Quality:Stable, lossless transmission ensures pure, sound with no noise.Easy Control:Front panel has switch to select fully-balanced or single-ended input/output; back has RCA & XLR interface.Wide Application:The device can connect with audio equipment that has no volume adjustment, very suitable for stereo system.Specifications:Material: Metal + Electronic ComponentsColor: BlackInput: 2-ChannelOutput: 2-ChannelConnector: XLR, RCAImpedance: 10K - 50KItem Size: 40*150*65mm /1.57*5.9*2.55inItem Weight: 320g / 11.28ozPackage Size: 200*180*55mm / 7.87*7.08*2.16inPackage Weight: 420g / 14.81ozNote:Volume controller only, other accessories in the pictures are not included.Due to lighting or other reasons, the picture and material object may slightly differ.Due to manual measurement, there may be deviation, please in kind prevail.Packing List:1 * Volume Controller.Package List:1 * Volume Controller