One of the top dogs in the pet harness industry is trumpeting a safety achievement for big dogs: a certified five-star crash test rating for the new Clickit Sport XL. The extra-large Clickit Sport, made by Sleepypod of Pasadena, Calif., is the only travel harness of its size to receive the Center for Pet Safety’s highest score, the company announced Wednesday. The Center for Pet Safety, based in Reston, Va., tests harnesses and other pet products submitted by manufacturers. The Clickit Sport XL is designed for dogs with a chest circumference of 34.5 to 40 inches, or up to about 90 pounds. The Center for Pet Safety used a 90-pound dummy canine model and a crash sled to measure Clickit Sport XL’s durability and protection. “Our research has returned findings that [extra-large] dogs can cause significant strain on the vehicle seat belt system,” said Lindsey Wolko, founder of the nonprofit organization. “Meeting the 90-pound crash protection level is a significant achievement.” Sleepypod holds a five-star rating for the Clickit Sport in all four sizes: small, medium, large and extra-large. Winning certification of the three smaller harnesses was easier, said Michael Leung, Sleepypod’s co-founder and lead product designer. The extra-large model required three years of engineering. “Loose dogs in autos are hazards for humans and pets,” Leung said. “A 90-pound dog can yield up to 2,700 pounds of force in a 30 mph collision.” The Clickit Sport XL features a padded vest designed to distribute forces and three points of contact to reduce forward and lateral movement in a car crash or sudden stop, the company reported. The extra-large harness is scheduled to begin shipping in August.