These sweaters were quite common during the late 1960s when I was in grade school.  It was the era when acrylics were just coming into everyday clothing.  By then, thick and fuzzy mohair sweaters had been the rage for a decade.  Then factories started making these brushed acrylic sweaters designed to look like mohair, but at a fraction of the cost.

They were an instant hit with parents, especially those with multiple children, as these sweaters looked trendy but were much cheaper. They weren't nearly as warm, but the parents weren't wearing them, so they weren't concerned.  Plus, mothers loved these sweaters because they could just toss them in the washing machine.

Kids liked them because they weren't as thick and bulky as wool sweaters and thus fit better under a jacket. Plus, being acrylic, they didn't itch like mohair nor wool, and could be worn over just a T-shirt.

This would fit a men's size small (38") rather well, up to about 40" which would be more of a snug fit. Val, who's modeling this sweater, is a size 38.