This David Clark H10-66XL headset is a variation of the H10-66 model, but comes equipped with the cool ENC (electronic noise cancellation) technology as well. It has 27 dB noise reduction but also gives you additional noise attentuation (17-22 dB) when the ENC feature is turned on. This helicopter headset has a coil cord and single U-174/U jack as well as a dual impedence switch that allows you to alternate between low and high impedance. I’ts powered by a 9 volt battery module (up to 25 hrs of continuous operation). The M-101 dynamic microphone is fitted on a flexible boom and the gel ear seals will provide you with additional sound protection while in the cockpit.