[COMPATIBLE DEVICES] Works with devices equipped with a 3.5mm AUX audio jack, including older smartphones, laptops, PCs, and some tablets. Not compatible with Lightning or USB-C ports [EAR SIZE] Ideal for users with small ears under 2.5in length. For users with normal or larger ears, we recommend choosing the medium-sized earbud for a more comfortable fit. [OPEN-EAR DESIGN] Resting lightly on the outside of your ears instead of inside them, the Resolve relieves ear fatigue and maximizes comfort. Listen privately to calls, music, podcasts, or videos, yet still hear your surroundings at the same time. [COMFORTABLE FIT] The Resolve's earhook goes around your ear while holding the earphones firmly over your external ears so that they stay as you move around. Since it doesn't go directly into the ear, it will not cause pressure or pain in your ear canals. [IN-LINE CONTROLS] The multifunctional in-line controls allow you to play / pause your music, adjust the volume up