Bluetooth technology to connect to a compatible Bluetooth device for hands-free communication and streaming. Clear voice transmission in noisy environments through noise-canceling microphone. Sound level sensitive function to perceive ambient noise and thus improve auditory situational awareness. Connects to an iOS and Android compatible mobile app, 3M Connected Equipment, which makes it easier to set up and adjust the headset. The mobile app notifies you when you need to change the ear cushions (hygiene kit) (frequency adjustable). Push-to-listen function to easily listen to the environment in seconds. Voice feedback after each setting adjustment. Auto power off after 4 hours of non-use. Battery type: rechargeable or disposable AA (run time approx. 70 hours).