The SEA-C100 is a 60ft of mini-din cable.
The SEA-C100 not only connects your cameras to your DVR, they also serve as a power source; making installation that much easier. To extend the SEA-C100, just connect them together. You can extend up to 300ft without problems. Please note, if you extend beyond 300ft, there is a slight chance you might lose some signal with every additional connection.