These are both 20 meter single band wire antennas (also available for other bands). This video reviews the “how it works” followed by tests for each, and explains how I got the Zepp to work. I particularly like the collinear (and, yes, it’s spelled with two L’s), which performs significantly better than my station vertical.
You can see a list of Ask Dave videos by clicking here. You can ask a question by clicking here. You can go to my YouTube channel by clicking here. And the tip jar is available by clicking here.