I purchased this product to deter some crafty squirrels and rats from eating our garden vegetables and fruits. It's been with me for a few days now, and I am happy with how it's working. It has deterred squirrels and rats in the area it is covering. Below is more detail on the why, the experience, and some tips. These types of products use motion detection to activate the ultrasonic deterrent. After some research, I preferred to buy it over the other possible options and also suggested by my friend. So i thought lets give it a try. In addition, it does not require an external power source as it charges itself via solar. To cover my garden area appropriately, I needed two detectors. I purchased this product and a competitors product (which looks like a robots head) from amazon. Here are the advantages I've observed with this repellent over the competitors: 1. It has a knob to adjust the frequency of the ultrasonic sound. 2. It has a sensitivity knob to adjust range. This let me focus on the area I was trying to target. 3. It still works without a hitch few days later. The other product has malfunctioned two days in. Here's some tips I've learned along the way: 1. make sure you adjust the frequency knob to the right frequency for your target animals 2. keep the detector in an area with sun, so it can charge 3. on first installation,