Clickit Utility is the first dog safety harness to incorporate three-points of attachment to absorb force in a frontal collision by dissipating energy and keep the dog in the car seat during an impact (patents pending). Clickit Utility can also be used in the cargo area and includes a d-ring on the back of the vest so it can be used as a walking harness.
Clickit Utility is similar in concept to the three-point seatbelt federally required in all vehicles. Straps enclosed in Clickit Utility's broad, padded vest hug the upper torso of a dog to absorb forward movement, while belts anchor the lower torso and reduce forward and lateral movement. The three-point design that secures the dog in its space diminishes the opportunity for collision with parts of the vehicle and passengers, and reduces the chance for traumatic injuries that can be associated with one-point dog safety harness designs that can catapult a dog's upper or lower torso forward into front seats, passengers and windows.
Start at the shoulder blades, wrap a string or measuring tape under your dog's arms and around the chest. Cross over where you started and continue around your dog's neck to create a figure 8. Mark and measure the length then look up the size on the chart.
Also check out the Sport Harness by Sleepypod. The new incarnation of the original design eliminates the need for anchors for an even easier use. Just Click n Go.