This ultrasonic mosquito repellent bracelet uses innovative bio-sound wave technology and accurately simulates the sound waves of female mosquitoes through the superposition of double wave rings. This provides efficient physical insect repellent action and effectively repels mosquitoes and cockroaches. The product is equipped with an intelligent USB fast-charging system that provides up to 30 days of standby time with a 30-minute quick charge, and can be used continuously for up to 90 hours, effectively blocking more than 80% of mosquito infestations. It has three intelligent scene modes, allowing you to switch between normal indoor mode, enhanced outdoor mode, and silent sleep mode with a single button, meeting the needs of different scenarios. The stylish and lightweight design provides all-round mosquito protection, whether you are working from home, exercising outdoors, traveling, or camping. It is an ideal choice for mosquito repellent use in the summer. Ultrasonic Mosquito Repellent Technology: Using bio-sound waves (ultrasonic waves + bionic waves), the dual wave ring superposition accurately simulates the sound wave frequency of female mosquitoes (effectively repelling male mosquitoes and cockroaches) and achieves efficient physical insect repellent effect. Smart USB Fast Charging: The built-in smart chip supports USB fast charging. A 30-minute charge is enough for 30 days of standby time. The battery lasts up to 90 hours and effectively blocks more than 80% of mosquito attacks. You no longer have to worry about frequent charging. Three-Speed Screen Mode: One click switches to normal indoor mode, a double click starts the enhanced outdoor sports mode, and three clicks starts the silent sleep mode. The sensor intelligently adapts to the needs of home, travel, and nighttime use. Safe Material: Made of skin-friendly silicone, allowing both adults and children to wear it with peace of mind. Full Protection: Stylish and lightweight design, whether working from home, camping and fishing, hiking and fitness, or outdoor picnics, it provides 360° mosquito protection for the whole family, allowing you to enjoy summer worry-free. Specifications: Battery Capacity: 80 mAh Charging Time: About 30 minutes Battery Working Time: 90 hours Product Color: White