[Built-in microphone and excellent compatibility]: S9 wired headset with built-in microphone is very suitable for online courses and voice calls. On-ear headphones support devices with 3.5 mm audio jacks, like Chromebook,Tablet, Kindle Switch, iPad, Laptop, PC. [Small, foldable and revolving]: Weighing only 7.1oz, 201g, our earphones will not add any volume to the childs ears; just fold them or fold them up, tighten the power cord, and you can easily carry the Hearphones with you. [On Ear Comfort]: these children's headphones have an on-ear design and soft protein ear cushions that provide comfort all day long. The full-size on-ear structure can also isolate outside noise, giving you a quiet space. [Adjustable headband]: Adjustable headbands provide impressive flexibility for your headphones, so they can adapt to the shape of your head for a perfect fit.