Passive Direct Boxes: This pair of DI boxes can connect any unbalanced audio signal Such as an electronic musical instrument or keyboard. It can also be connected from an amplifier speaker output to any unbalanced input such as a mixer. Attenuator switch box: Parallel output allows simultaneous connection to two independent inputs Direct Box: This direct box converts high impedance instrument output to a low impedance balanced signal Sound Attenuator: Attenuator switch corrects output signal level for optimal level match to connected equipment. Switchable ground lift eliminates ground loop hum problems. DI1 is a widely used single-channel passive impedance converter that can convert high impedance signals into low impedance signals. No batteries or phantom power are required. It is especially suitable for keyboard, electric guitar, electric bass and other musicians. Colour:Black Material:Metal Package Contents: 1 x Impedance Converter Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.