Two of these on ebay. They don't seem adjustable like the PRC-74 whip. What is their story? http://www.ebay.com/itm/271039671658?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649 http://www.ebay.com/itm/Military-Back-Pack-Radio-Antenna-PRC-104-Prc-174-/130744354483?pt=LH_DefaultDomain_0&hash=item1e70f886b3 73 Eugene W2HX