The GLOMEX round low profile antennas that look like shown here are non-directional type antennas. These sometimes comes with the built-in FM antenna as well. These type antennas doesnt seem to get very good reviews on how they perform in the real world.

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Being non-directional these antennas are only good for receiving TV SIGNALS from the local towns around 20 miles range away...
Of course these small round antennas look nice on the camper roof and is probably the main reason the manufacturers got away from the BATWING antennas...
The BATWING ANTENNA with the added dipoles like shown here are probably the best antenna you can get for picking up long range HDTV signals. Mine picks up digital stations from 60 miles and more away but you have to point the antenna to the local town that is transmitting the signals...

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Roy Ken