WIRING CONNECTION A. CONNECTING THE POWER CAUTION: AS A PRECAUTION, IT IS ADVISABLE TO DISCONNECT THE VEHICLE'S BATTERY BEFORE MAKING CONNECTION TO THE +12 VOLTS SUPPLY WIRING. 4 GAUGE (Thicker if planning for additional Amplifiers) wire is recommended both the power and ground wires. 12 Gauge, for the remote turn-on wire. Both types are available at most Mobile Audio Dealers or Installation Shops.