This bracelet is made from eco-friendly organic silicone, skin-friendly, by imitating specific sound frequencies to remove mosquitoes, suitable for baby, kids and adults, good choice when sleeping, reading and camping,etc. Features:Simple but stylish appearance, detachable and adjustable strap for your convenience. Made from organic silicone material, soft and skin-friendly, safe non-toxic, can rest assured use. By imitating the sounds that female mosquitoes hate, to achieve mosquito repellent effect. Can not only wear on the wrist, but also wear round your neck. Good waterproof dustproof performance, Protect the grade as IP65. USB charging, convenient and fast, no need to replace the battery. Lithium battery provide up to 150 hours of battery life per charge. Suitable for baby, kids and adults, good choice when sleeping, reading and camping,etc. Product name: Ultrasonic Mosquito Repellent BraceletFunction: Ultrasonic mosquito repellent;Strap Material: Silicone;Input: 5V/1A;Output: 34HZ-70KHZ;Battery capacity: 90mAH;Charging time: about 30 minutes;Endurance working time: 130 hours;Product color: black, white, black purple, white purple.Package List: 1 * Bracelet; 1 * Charging Cable; 1 * Instruction Manual; 1 * Strap.Principle of mosquito repellent: The bracelet achieves the effect of repelling mosquitoes by imitating the sounds that female mosquitoes hate, such as the sounds of male mosquitoes and dragonflies. In nature, the blood-sucking female mosquitoes are all in the pregnancy and egg-laying period. In this price range, Female mosquitoes will avoid male mosquitoes and avoid second conception. So simulating the sound of male mosquitoes can achieve the mosquito repellent effect.Product features: pure physical mosquito repellent, not chemical mosquito repellent, safer, more assured, more environmentally friendly and healthier. The elderly, children, pregnant women and pets can wear it. The product can be worn indoors and outdoors (by the sea, parks) , Camping, hiking, fishing).