ALEKO TS-BC13 3 Microprocessor Controlled Anti Bark Terminator The most effective bark control collar, High-frequency sound waves and static to stop dog's barking automatically Small and lightweight, Microprocessor controlled Voice recognition feature minimizes false triggering Effective on dogs from 4.5lb to 132lb Operates on a standard 6V Alkaline battery, High quality nylon strap adjusts from 5 to 24 inch