Effective Solar Mole Repellents According To Scientific Research, Animals Are Very Sensitive To Vibrations, And Even Small Vibrations Can Be Felt. Therefore, The 4 Pcs Animal Repellents Are Based On The Principle Of Vibration Wave Transmission, Ultrasonic Sound Is Sent Out Every 30 Seconds, Covering About 50-100 Square Meters, Which Can Effectively Repel Mice Hiding In Dead Ends.Safety And Environmental ProtectionThe Ultrasonic Insect Repellent Is Made Of High Quality Abs And Pvc. It Uses Low Frequency Sound Waves Which Are Not Harmful To Human Body To Repel Voles And Gophers Etc. Not Only Does It Use No Harmful Or Toxic Chemicals To Repel Rodents, But It Also Consumes No Electricity And Is Inexpensive, Long Life, Also Very Environmentally Friendly. Ip65 Waterproof & Lightning ProtectionThis Insect Repellent Adopts Professional Waterproof Technology And Has Superior Waterproof Performance, Which Is Not Only Safe And Convenient, But Also Corrosion Resistant. It Won'T Cause Pressure On The Ground Even After Long Hours Of Work.Easy To ChargeThe Professional Mole Repeller Uses High-Quality Polysilicon Solar Panels To Supply Power, Allowing The Sunlight To Charge The Battery Through The Built-In Solar Panels. It Also Has A Built-In High-Quality Environmentally Friendly Rechargeable Battery, Which Can Store Enough Power And Can Work Continuously For A Long Time After Being Fully Charged.Applicable PlaceThe Repellents Of Outdoor Animal Mole Can Protect Your Garden And Lawn From Moles, Voles, Mice, Rats Or Other Burrowing Animals. And It Has An Effect On 300 Square Meters Of Grass, Parks And Other Open Areas, But The Closer The Effect, The Better. (It Is Recommended To Use 2-3 Products At The Same Time, If The Garden Is Larger, The Effect Will Be Better)