Great alert and dog energizer
The original sensor lasted nearly 8 years before it failed, so I expect this one will too. It sends a signal nearly 300 feet from the top of the driveway to the house. In the summer, spiders occasionally build webs inside the photocell housing and stop the sensor from working, so I have to check it periodically and clean it out when that happens. Just in case we don't hear the alarm, the dog ALWAYS alerts us with a frenzy of barking in anticipation of a visitor. We see that as redundancy. It's a good little system.
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