Estone Wireless Sport Running MP3 Player Headset Headphone Earphone Earbuds TF SD Slot (Black) Built-in TF/ micro SD card slot support up to 8GB TF/ micro SD card( card NOT included) The wire free head-loop MP3 player is especially designed for sport lovers. Incorporating the behind-the-neck, over-the-ears design, this headset is extremely comfortable and secure for the most users: bicyclist, runners, joggers, walkers etc Designed fashionable and cleverish appearance, fine workmanship Separated earphone jack and power jack makes a convenient operation and faster transfer rate Built-in TF/Micro SD card slot