MT-S28 ,Notebook 2.0CH Speaker USB Power supply . CE/Rohs MOQ: 3000pcs ♦ ... noise ratio (Amplifier): >=95dBAConnect by USB and audio, For PC ,notebook ,MP3... *Built in low-frequency reactive radiation *High quality IC ... L):93*90*79mm *N.W.:0.475 KG (Around) Notebook 2.0CH Speaker USB Power supply