Thanks Mike.
I didn't go in detail and should because you never know who is lurking. I use marine epoxy where the cord goes in and will do with my other mats when I rebuild. I'm a fan of pvc and work with it off and on. 2in pvc is very stout and makes it easy to run the plug through the tube. Last 6 inches (at the mat) I will reduce it to 7/8s spilt duct flex tubing.