Ultrasonic Pet Trainer by Petsafe

Keep your pet safe with a collarless remote that helps you train your dog with sound. Allows you to train your dog off-leash with sound only, from a distance of up to 30 feet. Convenient, hand-held transmitter requires no receiver. Emits a high-decible, ultrasonic sound to discourage your dog from repeating negative behaviors. Also helps to reinforce commands without correction. Lightweight unit runs on one 9-volt battery which lasts through more than 5,000 activations.