Black out shades review
Lorna encouraged me to post this.
If you want to block 100% of the light coming in through your windows (and maybe also some of the sun's heat), then I sincerely recommend this:
I bought the ReflectSun EZ window covers because I want all the help I could get blocking some of the sun's heat too: https://blackoutez.com/Blackout-EZ-RV-Window-Covers/Blackout-EZ-RV-Window-Cover
My windows face directly south and don't get any shade. So I can tell you that as far as light-blocking goes, these really do block absolutely 100% of the light. Even during the brightest part of a clear sunny day, it's absolutely pitch-black in here with my lights off.
I can't really review the heat-blocking performance yet (I think I'll have to wait a couple of months for that), but the side that faces toward the sun is Mylar which is the same stuff used for thermal blankets.
So yeah, if you have any windows that you want to black out for any reason, then this is what you're looking for!
(Note: title was edited to clarify subject - there are no affiliate links here (they're not allowed), @TwoCables really liked these window covers. Posted with our blessing. ~lorna)