1. Anti-mosquito principle: The bracelet achieves the anti-mosquito effect by imitating the sounds that female mosquitoes hate, such as the sounds of male mosquitoes and dragonflies. In the wild, blood-sucking female mosquitoes are all pregnant and laying eggs. In this price range, female mosquitoes will avoid male mosquitoes and avoid the second conception. So simulating the sound of male mosquitoes can achieve the mosquito repellent effect. .2. Product Features: Pure physical mosquito repellent, not chemical mosquito repellent, safer, safer, more environmentally friendly and healthier. Old people, children, pregnant women and pets can wear it. .3. Three-in-one design: temperature measurement, time display and mosquito repellent in one. .4. The product can be worn indoors and outdoors (seaside, parks, camping, hiking, fishing).