Most animals have a wide listening spectrum, but only one is a more effective frequency. If the recommended settings don't work, you should set different frequencies to get the most for your specific needs. How it works: When an animal enters the area, an infrared sensor and ultrasonic repeller emits an ultrasonic wave converted to frequency so that the animal can escape from the area. Ultrasonic and Flash: This ultrasonic repeller has two modes of operation: ultrasonic and flash. A powerful LED flash to scare away large animals, such as raccoons, boars, gratings, etc. Applicable occasions - This mouse repeller is especially suitable for agricultural enterprises, rivers, nurseries and orchards. People perceive ultrasound. Keep the product away from living areas and areas where babies and children are active. IP 44 Waterproof - This product has an IP 44 waterproof rating. It can withstand normal rain from all directions, which means it is suitable for long-term outdoor use. (Tips: Do not expose the device to heavy rain, do not touch the charging interface).