Exclusive touch-sensitive Temperature Sensor System, increases vibration intensity as body heat is detected during use. Silky smooth, ergonomic shaft with larger head/tip. Quiet 3-motor system, choice of 10 vibration levels activated via push-button. Measuring 8.5 by 1.5 in., the Aiko is constructed of top quality, odorless, body friendly silicone. Lightweight, splash-proof and rechargeable via USB connection or A/C power supply. The heavy duty Li-ion battery allows for up to 3 hours between charges.