Command attention with these durable long-range megaphones. Adjustable volume control allows you to make announcements without overdoing it. Siren function is vital for emergencies. Convenient wrist strap makes it easy to transport. Battery operated for ease of use on-the-go (batteries not included). Adjustable 4 to 8 Watts. Audio Range: 400 yds; Length: 7"; Power: 4 W to 8 W; Power Source(s): 6 AA Batteries (Sold Separately).