Originally Posted by
Darth Lefty
A head or neck pad from a stroller, car seat, helmet, who knows? I circled back because I thought it might be a big horseshoe, the lawn game kind and not the actual horse kind, and I couldn’t think why it would be there.

Looks like the bottom piece from a full face motorcycle helmet. Note the ventilation exhaust on the back, to match the front intake vents. (bottom, in the pic)
It probably fell off the helmet of one of those chuckleheads who carry the helmet on the motorcycle for possible rain or passenger, but with no intention to wear it themselves.