THESE BELL AND HOWELL SOLAR PIR MOTION ACTIVATED ANIMAL RPELLER (TRADE NAME FOR VAN HAUSER LLC, ARE ADVERTISED ON TV AS "NO BATTERIES REQUIRED" BUT WHEN I RECEIVED THE ANIMAL REPELLER, THE THE INSTRUCTIONS ARE THAT THEY DO HAVE RECHARGEABLE BATTERIES, AND THERE IS A SWITCH THAT CAN BE MOVED SO ONE CAN REMOVE THE RECHARGEABLE BATTERIES AND REPLACE WITH ALKALINE BATTERIES. SINCE THE REPELLER IS SUPPOSED TO PRODUCE A SOUND THAT ONLY ANIMALS CAN HEAR IF THEY ARE WITHIN 30 FEET OF THE UNIT, I DO NOT BELIEVE IT DETERS ANY MOVEMENT AT ALL... read full review »