Sennheiser CX 6.00BT review: Great sound, comfortable enough for all-day use
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
SENNHEISER CX 6.00BT Bluetooth In-Ear Headset 507447 | eBay
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