Overheating in cars is one of the most common and dangerous health hazards affecting today's dogs. Even in mild weather, within minutes temperatures inside a vehicle can reach over 140 degrees, quickly leading to heat stroke. While we do not recommend that a dog ever be left unattended in a vehicle in the sun, these top quality Window Vent Grills will help keep your vehicle cooler, safer, and more comfortable for you and your dog, with less worry of an escape. Dogs also love to sniff the fresh air while driving! Window Vent Grills allow them to do so without letting them actually stick their head (or more) out of the vehicle - which can be dangerous and distracting. Even when dogs are restrained by seat belts, we advise that grills be used if the windows will be open at all.