This is cut and paste from Btech website. "The NA-701 is tuned to the amateur frequencies of 144/430MHz (* consider the NA-701C for higher VHF/UHF frequencies 155/455MHz)." So I went with the NA-701C to try it since GMRS is 462-467. I also like how flexible it is with how rough my kids are. Once I get my repeater up (hopefully today) I want to do some experiments with the stock and NA-701C antenna and see performance differences. Right now I am getting about a 1 mile urban range handheld to handheld. I can get 1.5 miles if I am in the right position but it is not reliable. Zero elevation difference. Very flat land. Single story residential neighborhood. I don't have a mobile or base to compare. Right now I have an antenna mount on my roof. If I am not satisfied with performance I may get a TV tower and get up to 35 or 45 ft. Prefer not to get into that investment if I don't have to. Guess we will see....