This harness incorporates the heartbeat technology adjacent to the dogs chest. Useful for dogs that have trouble walking calmly. The harness is also perfect for use in the car to prevent driver distraction. Walking Harness Comfortable and secureAnxiety Aid Houses pulsing heart against pet breastAppeals to natural instincts that produce calm when another heartbeat is nearAutomobile harness Effective seatbelt receptorHandy pouch Convenient for treats and waste bags so you don't have to carry themReduces aggressive walking tendencies Calming characteristics improve behaviours Small: dogs with chests 38-53cm/15-21