Amazon.com: RLSOCO Carrying Case for SENNHEISER CX Plus/CX True Wireless/CX 400BT True Wireless Earbuds : Electronics
Sennheiser CX 400BT true wireless earbuds offer up to 20 hours of battery life » Gadget Flow
Sennheiser CX 400BT Review: Simple Earbuds With Impressive Sound Quality
Amazon.com: Sennheiser CX 400BT True Wireless Earbuds - Bluetooth In-Ear Headphones for Music and Calls - with Noise Cancellation and Customizable Touch Controls, White : Everything Else