Designed for maximum omni-directional performance in the marine environment. Signal amplification allows for great VHF and UHF reception on 110V AC or 12V DC power! 21" antenna is ideal for longer range signals or increased performance. Includes antenna with built-in 1" - 14" nylon ferrule, power supply, 30' of RG59 coax, VHF/UHF band separator, and connectors. Two-year warranty.