K21 Business Bluetooth Headset, Sweatproof Bluetooth Headphones Wireless V4.1 Business Earpiece with Noise Reduction Mic Earbuds for Office/Business/Workout

Gave as a gift , they love it.

O microfone é bem potente, ótimo volume e isola muito o som externo, vem com algumas borrachinhas para melhor ajustar no ouvido e o melhor é a bateria pois usei no escritório mais de uma semana ouvindo música mais de 8 horas e ainda participando de conferências.

For me it is all about the battery life and with this one it is all day and more. sound is clear but I'm usually listening to books on take so not sure about music. Comfortable so this one is perfect for me.

Right away you will notice that it's kinda big and heavy. For you nerds it weighs 14 grams, which is about as much as a AAA battery weighs. Thick and bulky behind your ear. The tube that runs from the top of your ear to your ear hole is too long for me. The length, weight and bulk is why I am returning it. The sound and voice transmission is fine, which is why I gave it three stars rather than one. I am 5'9"; maybe if you are 6'5", or just have an unusually large head, this will be perfect for you.

I tested the new ear piece and the quality is great. I can listen to my Spotify music and when a call comes in I just click once on the ear piece and the call quality is great both from the call and caller side. If you want stereo you could buy one for each ear, but just one is great by itself. With just one, it allows you to hear any other nearby noise, which a headset blocks. Just one is also good is you want to hear music going to sleep without bothering a partner next to you. Spotify now allows you to set a timer for how long you want to play sleep music before it shuts off. Full charging time is just 2 hours.