I am using the Renogy 160W flexible panels and they seem to work great. They are much lighter and easier to mount but they are a little more expensive.
The first set I installed I used Eternabond tape and taped them right to the roof.
I then decided if I ever want to remove or replace them, it would be a pain removing the Eternabond tape. I went to Home Depot and bought some corregated plastic panels and cut them to about the size of the solar panels.
I then drilled holes in the plastic and installed a thread lug so I could screw the solar panels onto the plastic panels. I then used two sided Eternabond tape to attach the plastic panels to the roof.
If I need to remove the solar panel, I only have to remove 6 screws and unplug them.
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