Seat Heaters.

Those are baaaa D.

Those were the days very period correct. 

I miss my sheepskin seat covers!  

I had those luxurious covers for 15 years, mostly to cover up seats that didn't match my interior color, but they were cool in the summer, warm in the winter and turned 1-hour seats into 3-hour seats.  Maybe, someday, I'll get another set for my current seats.

And yes, those were very "in" on 356's when I was a kid.