Telex Communications, Inc. ANR 4000 Headset / Battery Power Supply Aviation HeadsetCat. No. 71060-101 (Helicopter)The Telex ANR 4000 Noise Reduction Headset combines design features of the popular Telex Air 3000 Headset with advanced techniques of electronic noise reduction.This unit is perfect condition in factory box and factory headset case.All original paperwork and Operating Instructions Included.