PIONEER SE-NC21M Noise Cancelling On-Ear headphones

Active noise reduction.
With excellent sound quality and first class active noise-cancelling, these earphones enable you to enjoy your music on the move without having to raise the volume in noisy places such as the tram, trains, buses and airplanes.
These earphones are equipped with a microphone that picks up ambient noise and shuts out up to 90%. A handy 'monitor' button temporarily turns off the noice-cancelling effect to enable you to hear your surroundings when needed.
1 AAA battery (included) is enough for up to 120 hours of noise-cancelling playback. If you can't replace your battery right away or don't need to cancel noise, you can turn off the function and use them as regular headphones.