This “enclosure” was my first attempt at being a Wireless ISP with no budget. The problem I was trying to solve was putting a waverider Subscriber module on top of a 150 grain leg. The Waverider unit was designed for indoor use. You would mount the unit indoors and then run hardline out to your antenna. In our use case, the 160 foot run of hardline would have caused too much loss.
So before you is the solution. We put an APC battery backup, netgear dumb switch, and a few POEs inside a cooler. A hole was then drilled in the side to pass ethernet and power cables through. This hole was then foamed and further sealed with silicone. This lasted for many years.