1. This machine should be installed at 80-120 centimeter away from the floor . 2. The installing point should be avoided from carpet, curtain etc., attaching sound material or else, the decrease of the sound pressure will do harm on the helminthes effect.3. It's normal that the mouse and vermin will increase at the beginning of the using days. Because they will get away from their living please after the attack of the ultrasonic.4. Use one unit per average-sized room with a pest problem.Additional units will be required in larger areas.5. Caution: moisture proof, waterproof6. Don't clean the machine by strong impregnant,water or damp cloth. Use dry and soft cloth with some neuter wash to clean the machine.7. Don't drop the machine and make strong striking on it.8. Using environment temperature: 0 to 40 degree celsius9. To increase the effect,you should use several sets machine at the warehouse or goods pilea-up, several rooms.10. Frequency ranges: 22-65Khz11. Ultrasonic frequency 120-150sqm of protectionSize: 95x60x50mmModel: 108Rated Power: 4WInput Voltage: AC 90~250VPlug Available: US PlugWeight: 42g