Basic information of ultrasound: Package Included: 4 packs Effective Coverage Area: 800- 1200 Sq. Appearance material: ABS flame retardant material Color: White Scope of application: can be used in a variety of environments Use effect Use 5 days, stimulate the insect nerve and scurry around Use 3 weeks, nervous system disorder Use 4 weeks and more to achieve insect repellent effect Warm tips 1.The ultrasonic emission port should towards the more open part of the room, avoiding obstructions with 1 meter in front 2. Keep distance from carpet/curtain or any sound absorption material that may reduce its effect. It is recommended to install this pest repeller at between 30-50 inches away from the floor for flying pests and 10-30 inches from the Ultrasonic sound can't penetrate furniture/cabinets/walls, please keep ample space around the area where it's. 3. It's normal that the insects and rodents will increase at the beginning of the using days, because they will get away from their living place after the infestation of the ultrasonic sound, and the pest repellent will drive them away completely for about 4-7 weeks later. 4. Clean the repeller with dry and soft cloth instead of strong impregnant, water or damp cloth dropping and striking should be avoided 5. Recommended for indoor use, it is better to use in closed condition