For anyone who can wire a light switch, this is an outstanding device. It is well made and easy for a home electrician to install. In my case, I put it on a double outlet box with a feed from main (grid) power and from a battery powered inverter. If the main power fails, the relay switches the power to the outlet. I use this to keep a deep freeze operating should the main (grid) power fail while I am away.Extremely well made. Super easy to install (if you can install a light switch).
Rating: [5 of 5 Stars!]