1.Special voice prompt,calling answer,voice notice phone number. 2. Military technology shell,Alloy steel,antiwear material. 3. Exquisite design,easy cooperating,portable . 4. Pneumatic pressure cone technology,neodymium iron boron speaker,perfect sound quality. 5. Dual power,built in 3.7v 500mah lithium battery,external dock 3.7v 1020mah battery,it can be used as power bank. 6. Bluetooth V2.1+EDR . 7. Using for meeting,travelling,car kit,children teaching,etc. 106*91.5 , 460g, 3.7V 500mAh; 3.7V 1000mAh