Review on Sony - C400 Wireless Behind-Neck In Ear Headphone White (WIC400/W) by Agata Asztemborska ᠌

The microphone is located on the left inner side of the rim, which is not a particularly logical location. The interlocutor won't hear you almost if you wear those throughout a conversation if they creep beneath the collar of your shirt, jacket, or other outer layer. Odd because the way the wire is constructed - why does it emerge from the outside and then be wrapped back inside - causes confusion. The right earpiece lasted a month less and I'm almost positive that the marriage was soldering contacts as the contact slowly faded. I treated them like a headset for a month (as the old ones were in 1 ear - due to quarantine) I failed to press the next song button while in neutral. I only suggest it for music. Yet, it is unlikely that you will remove them from your collar every time or unplug them from your phone when you make a call because doing so would be difficult. Overall assessment: do not advise.