Smart-Trek Mini Headphones with In-Line Volume Control and 3.5mm TRS Plug. Smart-Trek school headphones feature a durable and comfortable design, so teachers can have headphones that will function for years, and students can wear the headphones for an extended period of time. Its adjustable headband snaps easily into place to fit students of all ages. | Hamiltonbuhl | | Smart-Trek Mini Headphone with In-Line Volume Control and 3.5mm TRS Plug | Best Buy