[ Flexible Microphone ] : Featuring excellent voice pickup, this 360° rotatable microphone allows your kids to be heard in any environment, under any circumstances. Retractable design lets you hide it when not in use. Great for online calls, learning and more! [ Safe, 94dB Volume Limit ] : Rest easy knowing your child's hearing is automatically protected with the iClever headphone for kids. With an automatic limiting function, it will prevent any noises above 94dB from exiting the headphones so your children don't turn up the volume too loud in noisy conditions. [ Comfortable Fit ] : Your children grow and these headphones do too! Thanks to the adjustable headband, young children all the way up to teenagers can wear the expandable headband in comfort. Lightweight design and softy earmuffs make sure that they can wear the headphones for hours on end comfortably! [ Durable and Foldable ] : Ready to learn or talk on the road? Just fold them up and pack them in the bag, because the flexible headband allows the iClever children's headphones to withstand all sorts of abuse and still work fine. Plus, the premium nylon cord won't get tangled and withstands heavy use. [ Compatibility & Warranty ] : Use the HS21 headphones with any 3.5mm jack on devices such as Chromebook, Switch, iPad, Kids Tablets, Laptop, Smartphone, Desktop etc. Plus, you'll get an 18-month replacement warranty and friendly, 24-hr Customer Support Service!