Great quality product, amazing customer service, can't fault PerfectFit! We have LLM for our staffordshire bull terrier - he's slightly on the large side to standard possibly a cross and it is the perfect fit funnily enough. It's got enough room to grow with him, is lightweight and offers good control. He is a strong puller and it's definitely reduced it. The lead hoop is on the back which feels safer for when he pulls as it doesn't pull up into his chest/neck. He's happier because it offers him a bit more length on his lead. I measured him and ordered the recommended products we exchanged the chest piece for a bigger size (small for medium). I contacted customer service and they sent out the piece which I received within 48 hours (for free). We decided to keep the medium as it's adjustable and the small was just a few inches too small for his chest (the small has minimal/no adjustment at all). I packed up the small and returned back to Perfect Fit and it was so simple to do for the cost of postage. Would definitely recommend to others and was recommended to me by my parents who have 2 harnesses for their two dogs and have had them for 4-5 years and still going strong. Really great for long term use as the pieces are adjustable and customisable. Really great product thanks so much!