We are testing a new garmin antenna aimed at seeing 4.5-5 miles in the toughest conditions, most testing done so far has taken people who usually track 2.5-3 miles to 4.5-5.5 miles. This antenna utilizes a 6+ inch magnet, with radial arms and a tuned whip. While these are not on the market we have tester testing this in Va, NC, and FL. I am not scared to say on top of a mountain you could possible see 15-20 miles out of this antenna but has not been tested there yet. Stay tuned for more information and this antenna hitting the market as we are very close. You can see pics on facebook on Wilkins Outdoor Products, LLC. page.