It fits over another jacket, but it is also a jacket itself, not a coat. Maybe for running/sports, the description "lightweight jacket" would be appropriate. It does not have any kind of hood. It is extremely comfortable and satisfactorily warm (for a jacket, not a coat).

I could not in any case characterize this product as a jacket... It is a rather thin cardigan. It is relatively warm and has a good fit, but it cannot be used as the sole means of protection in cold weather. Good but slightly overpriced.