THIS PRODUCT MUST SHIP TRUCK FREIGHT AND DOES NOT QUALIFY FOR ANY SHIPPING PROMOTIONSShakespeare Style 4018-M VHF Marine19' LENGTH, 9dBPHASED 1/2-WAVE ELEMENTS IN A COLLINEAR ARRAY WITH A COAXIAL CHOKING SLEEVE TO SUPPRESS CABLE RADIATIONSame as Style 4018 with a special sleeve for mast mounting. Used primarily for land-based stations and on commercial vessels.The top choice for charter boat captains and experienced sport fishing enthusiasts. This long-distance VHF antenna is rigid enough to stay erect in rough seas, yet exceptionally lightweight.Brass and copper elementsChrome-plated brass mid section ferrules and aluminum sleeve bottom ferruleSO-239 connector at base Suggested mount: Mast mount using supplied 1-1/3 U-bolts. The 4018-M can be strapped to a larger mast if steel banding (not supplied) is used.Two sections: Base 162"; Tip 66":Shakespeare Limited Warranty: 2 yearsTechnical Specifications:Frequency:VHF Marine bandBandwidth:(within 2.0:1 VSWR) 3 MHzSWR:1.5:1 at 156.8 MHzImpedance:(ohms): 50Gain:9 dBMax Input (Watts):25DC Ground:NOTermination:SO-239Height (feet):19Polarization:VerticalRadiation pattern:Omni-directional