Please kindly noted that this item is sold by Ronen from Joybuy marketplace. Its 4m cable provides 2.8m of distance between each microphone for comfortable placement while the included tie clips allow for hands-free use. Feature: Omni-directional Polar Pattern: The omni-directional polar pattern provides excellent off- response even if a subject turns their head while speaking. Not all cameras have a microphone input. Verify this with your camera manufacturer. Many cameras have headphone remote control and other ports that look similar to a microphone input. Make sure that you are using the correct one. No need to install battery when using the microphone with a smartphone or a laptop. Install battery in right polarities when using the microphone with a camera or other devices (audio recorder amplifier etc.).