They are cut for various bands and so are various sizes with the largest being the civ air band which is about roughly 50cm each leg to 446 band which is roughly 20cm per leg. Options available do what they are described to do so for example the 2m 145mhz version is cut for the band and so will have a low vswr and so will be able to transmit on as well as receive, this goes for the 70cm and 446mhz version.
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