Feature: 1. Non Toxic: This mosquito repellent bracelet is more environmentally friendly and healthier than physical mosquito repellent. And It is suitable for pregnant women and babies. It is natural, non toxic and pollution free. 2. Smart: This electronic mosquito repellent bracelet can change the mosquito repellent gear according to the environment, and change the sound wave emission frequency to achieve the best mosquito repellent effect. 3. Stretch Tight: Easy to disassemble and assemble, the silicone bracelet is tightly wrapped with elasticity, and it is not easy to lose or tie your hands. 4. Lightweight: This anti mosquito wristband is light and portable, you will not get tired after wearing it for a long time, and it is very fashionable. 5. Waterproof: This ultrasonic anti mosquito wristband is waterproof and it will not be easily damaged whether it is exposed to rain or wet hands. Specification: Item Type: Mosquito Repellent Bracelet Gross Weight: 48g/1.7oz Material: ABS and Silicone Voltage: 5V Current: 1A Working Frequency: 34Hz to 70KHz Battery: Polymer lithium battery 100mAh (included) Charging time: About 30 minutes Working Time: 7 days when fully charged, 6 months standby Applicable Space: 5 to 10 square meter. Package List: 1 x Mosquito Repellent Bracelet ( Built in Battery) 1 x Manual1 x USB Power Cord