Admitted, it was probably in the stuff that arrived with the headphones but who expects something to go in 60 days. Here I am at the end of 2016 needing to replace that original pair (yes, that original pair lasted 5 1/2 years). Good sound, comfortable, easy to turn on/off, battery charge is long-lasting. Even above 60 Hz the bass will not rattle your ear drums in the Bengoos like my HD 280 Pros, but the bass is definitely pronounced and clear. Battery life holds up for her school and even afterwards. I bought it a little big because I wasnt sure how long it would take for my pregnant belly to shrink. I did not find a way to adjust it to make it look right. I bought this product to use it for Kitesurfing specefically, but it has some really really bad problems:1- After the Headphones went underwater, the sound quality became very low and distorted. El diseño del producto es simplemente genial, muy colorido y a mi hijo le encantó, viene un poco más grande que la talla habitual, pero él está creciendo y creo que le durarán más tiempo, vienen más anchas que los crocs normales, pero tampoco le encontramos inconvenientes, las volvería a comprar. I was sceptical when I found these on amazon as they are very well reduced from the normal price and wondered if they were fake.