Amazon.com: Sennheiser CX 3.00 Black In-Ear Headphone (Discontinued by Manufacturer) : Electronics
Amazon.com: Sennheiser Consumer Audio CX 6.00 BT Wireless in-Ear Headphones, Bluetooth 4.2 with Qualcomm Apt-X, 6-Hour Battery Life, 1.5 Hour Fast USB Charging, Multi-Connection to 2 Devices, Black : Electronics