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Product does what it says but is not robust. I installed it and used it at my video door-bell - electric lock system for one month. One day we experienced electric power outages in my area. This device was the only one that was damaged. I don't say that a product must be designed to withstand any disturbance at AC input, but the fact that the outages where not that severe and this was the only device affected shows that it has not even the slightest protection at input. Consider using it with some UPS or some other protection.