Unbeatable Active Noise Reduction Value - NOW FAA TSO Approved! The Echelon ANR™ 150 offers the same value and comfort features as the original Echelon, but with the addition of active noise reduction performance (21dB passive noise reduction, plus 14dB active noise reduction). Comfort features include patented three-position tension adjustment, low profile headband for even distribution of weight on the head, and detented sliders, which adjust the headband for a custom fit. You won't find a better headset packed with as many performance and comfort features as the Echelon ANR™ 150. The 18 oz (510 g) headset utilizes a high impact headband with stainless steel at the stress points for durability and lightweight comfort. Other features include volume controls for each earcup, a separate on/off switch to activate ANR, and stereo/mono select switch. Battery pack accepts one 9V alkaline battery (supplied) for 50 hours typical flying time. The headset collapses for portability and easy storage.