[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. [COMFORTABLE & SNUG FIT PERFECT FOR WORKOUTS] An ergonomic design with 3 different sizes of silicone ear buds ensures the optimum fit for your ears. The ear hook design gives a secure fit making it perfect companion for running, jogging or the gym. We've carefully crafted these earbuds to deliver a well-balanced sound with solid bass and an emphasis on mids and highs. Note: if you're looking for extra-strong bass you might want to look into larger headphones. [MULTI-FUNCTIONAL IN-LINE CONTROL] The included in-line control can control music play / pause, adjust volume up / down, previous / next track; moreover answer / reject calls, activate voice assistant and call last dialed number. (Note: The built-in volume control does not work on PC, laptop, or iOS MP3 players, and the volume up button