Purchase one for each vehicle and they lock and unlock in seconds. Red in color and the only way to safely travel with a pet. When even a minor accident occurs they can propel and incur injuries or be ejected. When first responders come to help you they often run away in fear and suffer injuries or are lost. You try to recover while not knowing where your beloved pet is or if they need help. Every single week a pet suffers while in a vehicle. These are great and easy to use and easy to see in case of emergency.