Audio signal level converter blow

AUDIO SIGNAL LEVEL CONVERTER
The converter guarantees high-quality output signal. Exceptionally durable, heat-resistant housing. (High-frequency output = speaker output) (Low-frequency output = amplifier output). Fits radios with output power: max 40W (music) per channel, min 5W (music) per channel.
Transmission ratio: from 3.6:1 V(in) max 14V
Input: 4 loose wires
Output: 2 gold-plated RCA inputs
INSTALLATION: Set potentiometer knobs to minimum. Connect wires:
green wire to left speaker +
brown wire to left speaker –
gray wire to right speaker +
black wire to right speaker –
Turn on radio supplying external signal to wires. Adjust signal level with potentiometers.