David Clark X11 ENC Aviation Headset New dual voice coil Electronic Noise Cancellation technology that reduces pilot fatigue Super-lightweight headband handcrafted from genuine carbon fiber for maximum strength and durability Intelligently engineered, low-force, dual-hinge suspension assembly that provides optimum articulation and personalized fit High-fidelity stereo ear phones with dual volume controls (stereo/mono switchable) Cell phone/auxiliary music input (three accessory cords provided)