Driving Safety Comes First: It prevents dogs from jumping out of the car window or moving around. Not only reduces the driver's distraction, but also protects dogs in case of a sudden stop. With seat belt lead clip, this harness set keeps your dogs under control while still have some range of movement and flexibility. (Buckle clip design, please refer to Product Description for more using instruction.) Easy to Use and Wide Compatibility: Fasttorelease buckles on both sides, it is easy to put on and take off. Put it on over cat's or dog's head, buckle it up, adjust the straps as you want, then attach the safety belt to Dto ring and fasten the seat belt. A safe trip starts from here! Detachable Seat Belt for Different Usages: Since the seat belt is detachable, you can use it in two different ways. With a seat belt, this set can ensure driving safety Removing seat belt, you can use the vest harness separately or attach the harness to a normal retractable dog leash. Simply but usefully. High Quality, Light Weight, Comfortable: Made of oxford fabric, 100 percent polyester, broad sponge padded chest plate. Industry standard premium stainless steel snap hook is electroplated for durability and abrasion resistance. The vest harness is lightweight and welltomade, with no burden on your pets. For Small and Medium dog Breeds: We have different sizes for choices, mostly suitable for small and medium breeds. Size Chart S: Length: 17CM or 6.69 inches, Neck: 24to35CM or 9.44to13.77 inches, Bust: 40to52CM or 15.74to20.47 inches, Weight: 2to5KG or 4.4to11.02 lbs M: Length: 23CM or 9.05 inches, neck circumference: 28to40CM or 11.02to15.74 inches, bust: 43to60CM or 16.92to23.62 inches, weight: 5to15KG or 11.02to33.06 lbs L: Length: 28CM or 11.02 inches, neck circumference: 34to55 or 13.38to21.65 inches, bust: 50to73CM or 19.68to28.74 inches, weight: 15to25KG or 33.06to55.11 pounds