I absolutely love, love, LOVE these jackets!! I started off ordering 4 of them. The Red Flag, the Blue Mountain, the yellow and the Black S in the larger size because I truly wasn't sure of her size because the charts on dog apparel aren't always accurate. That plus my dog is a Staffy so they have shorter but wider body frames. She also has been on a lower calorie diet and new exercise regimen so I knew at that moment she was right in the middle of 2 sizes. That lumped with the info that it would take a while to ship another size if needed, I got impatient when I saw that 2 of them were in stock as Prime items and would be here in 2 days! So, naturally I ordered 2 of the jackets in the smaller size. They do fit but were slightly snug. I was surprised how well it fit her Staffy frame. Being that the larger size were already on their way to us I decided on keeping all of them because in a couple of months she will definitely need the smaller size but until then I have the larger size for now! The size chart for these jackets is 100% accurate! They are not heavy winter coats but they are a fleece lined windbreaker! So they will keep your dog warm on chilly days but not for snowy days! They are easy to wash and easy to take with you as a "just in case" jacket. The seller is fantastic, easy to reach and eager to help! You can't go wrong with these jackets!! A great find!!Update: She now fits the smaller size so I ordered them in every color available! I love, love, LOVE these!!!