The Lenntek Sonix earphones are fairly average for their price. They work just fine. The sound is decent. The nylon braiding is definitely a plus for me as they prevent tangling. The downside to these earphones is that the ear pieces fall out quite often and can be easily misplaced. The package does include various earbuds of different sizes in any case. It also comes with a pair of plastic wrap arounds so that the earphones will stay on your ear. However, those pieces are also easy to lose. Aside from the nylon braiding, there is nothing special or different about theses earphones. This is just another one of those what you pay for is what you get kinda things. Battery Life Does not use batteries.