Amazon.com: Sennheiser HD 4.50 BTNC Bluetooth Wireless Headphones with Active Noise Cancellation, Black and Silver (Discontinued by Manufacturer) : Electronics
KUTOU Replacement Earpads For Sennheiser HD 4.50BT HD4.50BTNC Headphones Ear Pads HD 450BT 4.40BT HD4.40BT Earpads Ear Cushions
Replacement HD4.50BT, HD4.50BTNC, HD4.40BT Memory Ear Pads Cushion Compatible with Sennheiser HD 4.50BT, HD - Walmart.com
Sennheiser HD 4.50 BTNC Wireless review: A worthy Bose competitor at a better price - CNET