Main Features: 1. Inner rechargeable battery 2. Exsertile massage head 3. Extendable handle 4. High/ low power switch Functions 1) The exsertile massage head can help to massage muscles deeply; 2) Massage all area of body by sliding extendable handle; 3) Adjustable weak/ strong massage level; Technical Parameter 1) Power supply: AC100-120V/ 60HZ; AC220-240V, 50HZ 2) Power: 3.5W 3) Rechargeable battery: 2.4V/ 1800mA 4) Vibration speed: 5000rpm( strong) ; 4000rpm( weak) 5) Charging time: 12 hours