Non-toxic and safe: This rechargeable mosquito repellent bracelet uses skin-friendly silicone, which is non-toxic and harmless, does not contain harmful substances, has no odor or harmful substances, and is suitable for babies and adults.Ultrasonic-Ultrasonic technology uses biosound waves (ultrasonic waves + bionic waves) and superimposes double-ring sound reproduction to imitate the sound of female mosquitoes (male mosquitoes, cockroaches), thereby achieving the purpose of repelling mosquitoes.Multi-mode selection-Press the switch once to start the indoor mode; press it again to switch to the outdoor sports mode; press it a third time to activate the silent sleep mode; press it a fourth time to turn off the device.Wide range of uses: This mosquito repellent bracelet is stylish and lightweight, whether you are indoors or camping, fishing, hiking, sports, barbecue, it is very suitable, it can protect you, you and your loved ones, mosquitoes, and enjoy a perfect summer.