• Humanistic ultrasonic bark control device that helps control excessive and abnormal dog barking. • Automatically detects barking and emits a safe and harmless ultrasonic sound. • Durable material, waterproof, shockproof, and weather-resistant. • Small, lightweight, easy to install, place, or hang anywhere. • Maximum effective range up to 33 feet away. • Suitable for all breeds and sizes of dogs. • Size: 3.34in x 2.83in x 3.54in. • 1500 mAh rechargeable lithium battery, fully charges in 5 hours, works for 30 days. • Not recommended for dogs over 50 pounds, under 6 months, or over 8 years old.