Dyson OnTrac customizable active noise cancelling headphones. 8 Active Noise Cancelling microphones cancel up to 40dB of unwanted noise, for fully-immersive listening. So you don't miss a beat.(1)Based on average listening time of 3 hours a day with Anc on. Performance may vary based on environmental conditions and usage.(2)With Anc on. Performance may vary based on environmental conditions and usage.