(5 pack) Freeze Miser Outdoor Faucet & Spigot Freeze Protection – Patented Valve Shield, Activates at Water Temperature Below 37°F/3°C – Durable Winter Cover Alternative – Quick Install, Saves Water – 1 Pack

I really like this product. It protests my pipes from freezing and does not rely on power. Just screw it on a spigot and turn the spigot on. No water will come out when it is warm but when it gets down to about 35 it starts to drip. I acts on the internal water temperature. As the temp gets closer to freezing the drip gets faster and it shuts off again if warmer water gets to it. All done automatically . I have three of these in service. Two for over two years. No problems at all since I learned about these and put them in action.