PHASE III 6396-AIS-R 4' AIS Antenna 3dB Gain. Specially engineered for the extra bandwidth required by AIS transceivers, this Phase IIIT antenna enables reliable communication over marine VHF frequencies.. Silver-plated outer conductor, copper inner conductor. Stainless steel mounting sleeve. SO-239/PL-259 connector. Specifications. Max. Power Input: 50 watts. SWR: Less than 1.5:1 at 162 MHz. Bandwidth: 5 MHz within 2.0:1 VSWR. Frequency: VHF AIS Marine Band. DC Grounding: Yes. Pattern: Omnidirectional. Polarization: Vertical. Specifications:. Length (Inches): 48'. DB Gain (dB): 3db. Construction: Fiberglass. Color: White. Cable Length (Feet): n/a. Antenna Band: AIS. Box Dimensions: 2"H x 2"W x 58"L WT: 2 lbs. UPC: 719441200688