Introducing a new type of earphones: The INAIR ERGONOMICS EAR SPEAKER M360bt (Color: Black). There is adhesive residue from a price tag on the upper right front (please refrain from purchasing if you are concerned about this). You can find many highly-rated reviews by searching for "INAIR M360bt". The following is an excerpt from another website: The main feature is the "M360bt," an in-ear ear speaker that achieves a unique fit. The entire spherical driver unit located at the tip is covered from behind by a newly developed biocompatible high-tension silicone "AIR TUBE," and the outside is wrapped with a spherical soft sponge "in-ear cap," creating a three-layer structure of different materials to produce a sound with breadth and depth. In addition, by eliminating the "sound tube" found in canal-type earphones, the newly designed "AIR TUBE" with a large open front delivers sound directly to the entire inner ear without blocking it, while also suppressing sound leakage to the outside. It has a structure that is as resistant to sound leakage as general earphones, allowing it to be used not only indoors but also in fitness gyms and during commutes. Furthermore, it uses a body made of aluminum that has been machined to increase rigidity and strength. The driver unit is equipped with a 6mm dynamic driver. The Bluetooth version is 4.1, and the supported codecs are SBC/AAC/aptX. Battery life is approximately 5 hours of continuous playback, approximately 7-8 hours of continuous talk, and approximately 300 hours of continuous standby.