5mm fitting, meaning any aftermarket cable will have to be trimmed down to try and get it to fit into the hole area. The sound quality is better with deeper bass and clearer voice, even compared with high end brands. Even more to that, I love how portable these are! Dabei hat sich nicht nur das Logo, nein, auch das Band, welches komplett um die Sohle des Schuhs geht, gelöst. My grandson is a BIG time fisherman so when I saw these on Amazon this summer I put them on my Amazon Christmas list. The phone offers Advance sound settings where I can customize sound quality and effects. I havent carry anything yet, will see how good quality they are not at the moment, dont even want to rate 1 star. I did have to double up on drill bit holders/extenders to use a drill for the top screw, with the hook being in the way; so I knocked off a star for poor placement of that hole. I?m in college and I?m very particular about not losing socks. First time you click it your phone will ask you which assistant you want it to activate ( i have Amazon Alexa and Google Assistant).