I bought this thing several years ago at an REI garage sale. The base is in the neighborhood of 33" x 40", and it’s made out of heavy-duty stuff. I have no clue whether all parts needed are included, as I’ve not tried to put it on a car top. I had thought my boyfriend could use it in the bed of his truck when it was raining. But he turned his nose up at it, and it has languished since in its own little purgatory.
Labeling indicates it is a Sherpak Go!
Edit: btw-it’s FREE.