Those things just look like a moisture holder and rust will be your result. I store my bikes in my garage, I live in Florida and I run a fairly heafty fan, to keep the air moving. In the summer, the humidity and temp in my garage are 70 to 100% with temps during the day over 110 and at night, in the 80's. I would never store them outside in something like that. Now you could be in the desert SW and humidity is not a problem where those might work, but I would go with some more substantially built, and have the ability for some air movement.