Defean Replacement HD4.50BT, HD4.50BTNC, HD4.40BT Memory Ear Pads Cushion Compatible with Sennheiser HD 4.50BT, HD 4.50BTNC, HD 4.40BT Bluetooth Headphones - Walmart.com
Amazon.com: Sennheiser HD 4.50 BTNC Bluetooth Wireless Headphones with Active Noise Cancellation, Black and Silver (Discontinued by Manufacturer) : Electronics