[yongjik]

Maybe I'm missing something super-recent, but for second graders, a "cat seat" is basically a piece of plastic for them to sit on so that the seat belt passes on their chest, instead of neck, which would be disastrous in case of accident.

Unlike toddler car seat, these seats don't look huge by any means, compared to the kids sitting on them. (Well I guess it's still problematic to sit three of them in a row in most cars, but that's a separate discussion...)