Although DT offer the full width, vehicle specific, box for the BMW X5, we opted for the DT9 500mm wide Box which is the perfect size for our Parson Russell Terrier. And it still leaves plenty of boot space for luggage, shopping etc. We are super happy with the quality of our Box, it's robust, it's crash tested, it's easy to move in and out of the car, it's easy to clean and it can be locked. Most importantly, Freddy is happy, comfortable and safe travelling in it. The help I received on th...