Let me present you Mio's headphone, the k701 : r/k_on
Anime and the love of Headphones – animananime
Mio, k on, music, headphones, smile, lipstick, kawaii, cool, anime, anime girl, HD wallpaper | Peakpx
Fun fact: the AKG K-701 headphones that Mio wears received a big boost in sales when K-On! aired and retailers unofficially named it the "the Mio-phone" : r/k_on