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.