I bought this coat with the "Caution" small vest harness (also reviewed) for my reactive 5kg Yorkie-Pug cross and will be using it in winter. It has a soft fleecy underside so would be too warm for my thick-coated dog in summer. It's a perfect fit and unlike some dog coats which can be over-engineered, the design is simple and effective. It only takes a couple of seconds to put on and take off, it allows the dog full movement, it's light, and it has a slot on the back so you can attach your lead to your harness, if the harness is being worn under the coat. It also seems very good quality. Delighted with it.