Attaches directly to your dog's harness and then clicks into the female slot of your car's seatbelt system. With this system, you do not have to undo the seatbelt every time your dog gets in or out of the car, you can simply leave it clicked in between trips. With the carabiner's swivel action, your dog won't get tangled in the seatbelt. Tether extends from 15-22 inches for a broader range of movement. Swivel action for tangle free mobility. Universal fit for most vehicles. Incompatible with Volvo. Not recommended for Ford F-Series vehicles. Designed to prevent distracted driving, not crash tested.