The hardest part of adding a subwoofer is the installation and connection of the amplifier, with our new Rapid-Fit wiring kits the process is made very simple indeed. The Rapid-Fit kits allow the installation of power direct from the interior vehicle fuse box and high level signal input to the POWERBOX400.1M-V7 directly from the factory headunit so there is no need to run power cables through the vehicle firewall / bulkhead. The kit features a fused spur for Rapid Fit power installation into vehicles internal fuse box and unique wire clip connectors for fast and easy connection to speaker wires for high level amplifier input. 2.5 Meters long