PetSafe 9 m ultrasonic remote trainer

This training system uses ultrasound that is activated by the master to show the dog what behavior is acceptable. If the device emits an ultrasonic sound, i.e. a "negative" sound, the dog understands that he must stop what he is doing, because it is unacceptable. In addition, the system also contains a "positive" tone, with which you can praise your four-legged friend when he is good! The device is battery operated, has 2 switches, works up to a distance of 9 meters and does not require a receiver collar.