21'-5" tall 4 band (10-15-20-40 meters) HF vertical antenna is constructed of 1-1/4" heavy wall high strength corrosion resistant aluminum tubing, aluminum mounting bracket and low loss high strength isolators. Broad-banded for a low VSWR and will handle full legal limit transmission on SSB or CW. Easy to assemble, clamps onto poles. Includes Stainless Steel clamps and hardware that will provide years of trouble free service. Requires single 50 ohm coax cable.