This is the one I got (for the hatchback), I believe the medium size. It does the job (you have to lower the visors to hold it in place), but I whack the passenger with it every time I take it out.
Are you talking about one of these?
https://www.amazon.com/gp/product/B01KIFISX2/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
If so, that's what I use for mine.
This fits perfectly, (Specify Standard size, 64" x 32")
It's on sale now, plus you can clip a coupon for additional 5% off.
Black on one side and silver on the other:
https://www.amazon.com/gp/product/B01KIFISX2/ref=ppx_yo_dt_b_asin_title_o01_s02?ie=UTF8&th=1
Circular works wonders! When folded up, it fits in the door compartment of my tiny Hyundai Elantra. $16 on Amazon