Physical Repellent Ultrasonic Technology: Change the frequency using ultrasonic theory to stimulate the auditory system of mosquitoes and other pests and make them unbearable and uncomfortable. No stimulation to people and pets. 20-50 kHz Ultrasound: High frequency ultrasonic circuit, not only for mosquitoes, but also most rodents, such as insects such as cockroaches, ants, spiders and mice. No of added chemicals: no radiation, harmless, non-toxic, with wide coverage, ultrasonic waves cannot pass through walls. We recommend that you install one device for each room. Night Mode: Plug in the repeller and an LED lamp will light up as a small night light to give you night security. Widely used and energy saving energy: It can be used frequently in houses, apartments, restaurants, etc. and is used for insects, rats, mosquitoes, flies, wasps, ants, spiders, fleas, cockroaches, low energy, but it is very effective. toxic. There is no impact on people and pets.The pest repeller should be installed at a height of about 30-120cm from the ground at a 90 angle.Specifications:Frequency: 22-50 kHz.Power: 3 W.Material: ABS plastic.Dimensions: 14 x 7 x 7 cmIncluded in delivery:2 x ultrasonic insecticides1 instruction manual (English language not guaranteed).Note:1. Keep distance between carpets, curtains and auMaterials that absorb noise and reduce the effects.2. Rats and pests begin to use. This is normal as they escape from their habitat after a sonic attack. Normally it takes 3-4 weeks to get results.3. Do not clean the pest control device with water. Use a soft, dry cloth.