Effective: Once The Pets Enter The Protection Range, The Pir Sensor Will Start To Work, Then It Will Emit Ultrasonic Waves, And The Red Light Will Be On So That It Will Repel The Pet.Energy Operated Solar And Waterproof Design: This Ultrasonic Cat Repellent Can Be Powered By Solar Power Under The Sun, Which Is Economical And Environmentally Friendly. Larger Detection Area: Pir Infrared Motion Sensor Has An Angle Of Up To 50 Degrees And A Detection Range Of Up To 8 Meters. Large Detection Area Up To 230 Square Meters. Get Rid Of Animal Droppings, Food Destruction, Noise And Footprints In Just 1-2 Weeks.Easy To Install And Use: You Can Simply Push The Animal Repellent Into The Ground , Or Hang It On The Wall Through The Back Slot (With Direct Sunlight Recommended)Tip: If You Turn On The Cat Repellent When You Receive It, There Is No Response. Please Charge It In The Sun For About 2 Hours And It Will Work.