With its tunable design and top loaded coil, this durable antenna features a Superflex 1/4” fiberglass rod and 180° whip action capability for superior performance. Designed for CB and 10 meter radios, it delivers great range and clarity anywhere the road takes you. Trust K40 Antennas and Accessories – for confidence that comes with a guarantee. Frequency Range 26-30MHz ¼ Wave Length Design Chrome-Plated Whip Adaptor Fits All 3/8” x 24 Threaded Mounts Can be Used as a Single Antenna or Co-Phased MODEL NO - SF-300