Pasive DI Box. The Pro Co TradeTools CB1 is a simple passive direct box that offers clean, reliable performance with nearly any unbalanced signal source, including electric bass, acoustic guitar pickups, keyboards, drum machines and mixer outputs. High Input Impedance Minimizes Source Loading for Maximum Performance; Floating Transformer-Balanced XLR Output for Maximum Isolation; GND/LIFT Switch Eliminates Hum and Buzz; Handles Line-Level Inputs to +20 dBv at 20 Hz; Flush-mounted Switches and Connectors Resist Damage; Passive Design Requires No Batteries or Phantom Power; Rugged Pro Co Uni-Box Construction Provides Protection and Shielding. Dimensions: 124 x 111 x 44 mm. Weight: 0,46 kg. Color: Blue.