Intelligent noise reduction:Automatic noise reduction, clear sound amplification. High-power speaker with a volume of up to 120 decibels. Working at heights makes it more convenient to patrol and speak. Small and light:With its compact size,even toy aircraft can carry the product. Long battery life:Built-in large-capacity lithium battery, fully in 2 hours, can work continuously for 4 hours. Ultra long distance transmission:The communication distance is up to 2KM, making high-altitude sound amplification easier. communication:Not limited by the communication of the aircraft, built-in polymer lithium battery, 10 hours standby. Item Name: Mini Wireless Communication Distance: 2-3km Impedance: 2Q Power: 5W Frequency: 433MHz Built-in Battery: 4.2V Lipo Battery Charging Voltage: DC 5V Charging Time: 2h (The product appearance and printed words depending on the batch, but this does not affect use) Colour:As Shown Material:plastic Package Contents: 1 x Walkie Talkie Speaker Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.