Sennheiser's new wireless headphones build on its popular HD 4 series | Engadget
defean Ear Pads Cushion Replacement, Earpads Compatible with Sennheiser HD 4.50BT, HD 4.50, HD 4.50BTNC, HD 4.50SE, HD 4.40BT, HD 4.30G, HD 4.20S, HD 458BT, HD 450, HD 450BT, HD 400S, HD
Amazon.com: Sennheiser Momentum 4 Wireless Headphones - Bluetooth Headset for Crystal-Clear Calls with Adaptive Noise Cancellation, 60h Battery Life, Lightweight Folding Design - Black ) : Electronics
NeweggBusiness - Sennheiser HD4.40 BT Bluetooth Wireless Headphones