K40 Superflex gives you 180 degree whip action capability. The SF-400 features a tunable design with top loaded coil, and can be used as a single antenna or co-phased. This black fiberglass CB whip antenna is designed for CB and 10 meter radios, and has a frequency range of 26-30MHz. Superflex 1/4" Fiberglass Rod 1/4 Wave Length Design Fits All 3/8" x 24 Threaded Mounts Chrome Plated Whip Adapter Mil-Spec Polyolefin Sheath MODEL NO - SF-400