Feature: 1. Behavior Training: The device helps with barking training and behavior assistance, preventing your dog from chewing, digging and other destructive behaviors. 2. Electronic Dog Whistle: With sound and 3 ultrasonic modes, the frequency is 25 to 30 kHz, which is hard for human to hear, specially for dogs. 3. Flashlight Function: Also has a flashlight function, with high brightness and 3 lighting modes, allows you to better use it at night. 4. Safety Design: The barking deterrent range can up to 16 feet and be turned off as a safety function after 10 seconds. The device is safe for dogs of 5 to 120 pounds, 6 months to 8 years old. 5. Long Battery Life: Built in a 1200mAh battery and can work for up to 30 days without recharging, compact design is easy to carry and use indoors and outdoors. Specification: Item Type: Ultrasonic Anti Barking Device Material: ABS Ultrasonic Frequency Range: 25-30kHz Battery: 1 x 18,650 1200mAh lithium ion battery (built in). Package List: 1 x Ultrasonic Anti Barking Device1 x Manual