Syllable In-Ear Wireless Sport Earphones uses Bluetooth 4.0 technology in order to have a clear 3D stereo sound. Because the earphones are wireless it’s really very convenient to listen to music while you need to use your hand do other things.Due to latest version of Bluetooth you can clearly speech with your device from up to 35 feet. The battery life of the device can last up to 5 hours. When you have a fully charged earphone, you can have about 180 hours standby time and need 1-2 hours for charging time.Fully charged the earphones should give you roughly 4 to 5 hours of listening/talk time. Syllable In-Ear Wireless Sport Earphones is comfortable and secure and as design fits perfectly to your ear; the cable smartly stays out of your way when running, jogging,or exercising.
The earphone is equipped with CVC Noise Cancellation 6.0 technology, which reduces the outside noises and guarantees HD stereo sound quality. It also supports stereo loss less music and answer calls. It has universal compatibility and can work seamlessly with your iPad, iPhone, iPod Touch, Android Smartphones, tablets, Windows laptops, desktops, chrome Books,Bluetooth speakers and more.
SPECIFICATION
Bluetooth version: V4.0
Frequency range: 2.4GHz – 2.48GHz
Operating distance: up to 10m (free space)
Standby time: up to 180hrs
Talking/music-playing time: about 4~5 hours
Charging time: about 1~2 hours
Bluetooth profiles: A2DP, AVRCP, HSP, HFP
Frequency response: 20 -22kHz
Operating Temperature:-10C~50C
Review
So, now that you learned about the Syllable In-Ear Wireless Sport Earphones, what they are and what they do, let us see a real review in real life.
Package
The earphones came to me inside a plastic bag, well protected. Inside it there was a box, protected with plastic, very tight. The box, covered in black, from the one side you can see a photo of the earphones and on the other sides you can see various information about the earphones as specification, characteristics, etc. From the side you can see what each button does at the earphone mic. Also in the same place is the usb port for charging the earphones.
After opening the box, inside you can find the D700-2017 Bluetooth Headphones, two replacement pairs of earbuds, a USB charging cable, a user manual and a QC pass control sticker. The manual explains in details how to work with the earphones which is written in plain English and is easy to follow.
Design
The earclips as you can see and in the video, they must be made from something soft, I guess some pliable plastic. The earphones have a rotatable design which makes it more easy to find a comfortable fit on your ear. The earcups are made from soft rubber. Counting the 2 pairs that are apart in a small plastic bag, you can see that each earcup has a certain size, so you can use small, medium and large size. If you want to change them is very easy. I must mention that despite the size of the whole construction, they are impressively lightweight, as they weight only 18 grams!
The two earphones are connected with each other through a small cable of 72 cm length. Somewhere in the middle (not exactly in the middle), is the control unit for the earphones. The control unit has 3 push buttons on it, 2 for for volume up and down or for track shuttle backwards and forwards if you use them for controlling your music player and a middle button which is for accepting calls. The earphones can be used for answering to calls of course as it has built-in microphone. The middle button can be used for on/off and Bluetooth pairing for the first time. 
Connectivity and charging
In order to charge the earphone you will need the cable that comes with the package. You will have to stick it in the mini-USB port at the control unit. You will need 1-2 hours for full charge. A small LED on the control unit lights up red when charging, and then switches off once fully charged. The same led blinks when you try to pair the Syllable In-Ear Wireless Sport Earphones with your mobile or pc. Pairing these earphones with a Bluetooth-enabled device is very easy. Switch on the earphones, then press continuously the middle button till you see the led blinking, start your mobile to search for nearby BT devices and that’s it!
Audio
The earphones are well-tuned for music as well as voice.The sound is full, without being bass-heavy, but doesn’t over-blow your hearing with loud treble.The mid-range is clearly defined and detailed, piano, synths and guitars sound good. The treble range is decent too, with nicely crisp and clear high notes. Vocals are well defined and clear. You can easily hear music out in the crowd or in the metro. As the earcups fit in perfectly, you can hear everything perfectly, without any loss.
Conclusion
I am very impressed of the great sound quality D700-2017 Syllable In-Ear Wireless Sport Earphones have, how light they are, comfortable and with long lasting battery life. The price is definitely very good and I guess is hard to find BT earphones at such a good quality at this price. I would propose them for sure for anyone that wants to have BT earphones with a very good quality!
Check the video presentation below