I don't quite see how they can pop off, they are under the deck, not on top. The shock cord is pulling the composite tube up against the resistance of the deck. I have had traditional style Maroskes on a boat that I had on a car roof for 8 hours a day in the middle of summer and there were no problems.

Ric

: I hope you have better luck than I had with deck hardware only
: glued with epoxy.

: Epoxy will soften and fail in high heat situations, like when your
: boat is on the car or
: sitting on shore on a hot summer day. On the water is probably
: cooler.

: If you can't hold your hand on the deck because the sun has heated
: the dark colored wood,
: epoxy alone may fail. That's why I only rely on screws or bolts.

: Rob