I have a Saris SuperClamp 4 platform bike rack that is made from steel. I was worried about having two fat tire bikes and my brake lights covered with and without the cover on the ebikes. I also have a 4-way flat harness with my 2" hitch and added AUX light that attach with magnets to the hitch:
https://www.amazon.com/gp/product/B00GR7P55A/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
I have the Sarris rack on my smaller SUV; but, you can see the AUX lights bottom/center with extra long Velcro straps connected to 4-way flat. You can see my vehicle brake lights a little better with my larger 7 passenger SUV; but, the Amazon cover with the brake light panels still covers most of the rear area. I usually remove the seatpost and rack bags when heading out of town.
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