... .5 Headphone Jack High-Fidelity Magnetic Speakers Noppal 768 Portable Active Mini Speaker For Micro SD/TF Card, MP3, Mobilephone, PC 1 ... :≥80dBOutput: 3.7V*4.2VInput: 5.0V Noppal 768 Portable Active Mini Speaker For Micro SD/TF Card,MP3,Mobilephone,PC