This is an old, old full size down comforter, maybe 30-40 years old. It leaks down and tiny feathers copiously. You should not try to use it as a comforter unless you have really good repair skills, not even inside a duvet, because it will continue to dribble its contents out all over the place. You could use it to stuff something anew.
If I haven't utterly discouraged you, please let me know when you'd like to pick it up. Contactless porch pickup in Wallingford.