The antennas sold by Extreme Networks come with a LMR cable attached to the antenna. The best practice is to use the cable that comes with the antenna. If the distance between the antenna and the access point is longer, then use LMR cables produced by Extreme Networks.
Note
Determine the distance between the locations where you intend to mount the external antenna to ensure that you order the right cable length.
Tip
The best practice is to use a smaller length LMR cable.