SODIAL(R) Hot Sport MP3 Music Player Wireless Handsfree Headphones The item don't Built-in memory card, but Support TF card memory extension up to 8GB Sport MP3 Headset, designed for comfort and convenience while walking, jogging, exercising. Handsfree In-Ear design S/N Ratio: &gt;=86db Output Frequency: 20Hz - 20KHz