We have been on the hunt for a comforter that will fit inside our king sized duvet and the Winfield 300 Thread Count Cotton Percale Luxury Down Alternative Comforter does! This fact alone makes it 5 stars for me!! I also love that this is a down alternative, which is important to me. This comforter even has corner tabs for thing into the duvet cover. This is a little too warm for late spring and summer, but wonderful for those cold New England nights. I am thrilled to have found a comforter that is down alternative and fits inside our duvet cover.