The HANC100 is a Noise Canceling Headphone that can Produce a 75% Noise Reduction when in the Active Mode. It also has 50 hours of use on one AAA Battery. The HANC100 also has a Cord Rewind System, so that it will retract its 4.9 foot cord back up into its left earpiece. And to make it easy to travel the HANC100, folds down into a compact size for easy traveling. And when you are not traveling the HANC100s can be used in the Passive mode for Great Performance at Home.