2 pieces electronic mosquito repellent indoor fly repellent ultrasonic mosquito insecticide home mosquito intelligent artifact Ultrasonic physical repellent technology: uses the principle of ultrasound to change frequencies and stimulate the hearing system of pests like mosquitoes, making them intolerable and uncomfortable. No stimulation for humans and pets. 20-50khz ultrasound: high frequency ultrasonic circuit, effective not only against mosquitoes, but also against most rodents, such as cockroaches, ants , spiders, mice and other insects. No chemical addition: no radiation, harmless, non-toxic, wide coverage, ultrasonic cannot pass through the wall. We recommend one device per room. Night mode: Insert the insect repellent, the LED will light up as a small night light to provide you with safety protection at night. Wide use and energy saving: can be used frequently in home, apartment, restaurant, etc. And used for insects, mice, mosquitoes, flies, wasps, ants, spiders, fleas, cockroaches, low energy, but very effective. Product size:6.1* 10*3.3cm Delivered quantity: 2 Warm tips: The color may be a little deviation due to light and monitor and other issues. Due to manual measurement, the product may have an error of 1-2cm. This is a normal phenomenon. Thank you for your understanding!