I'm giving five stars even though it has a couple of design quirks, because nothing else I've seen comes close to what this can do.I have it mounted on the top of a 1000 gallon water tank, somewhere between 150-200 feet from where the receiver sits on the far wall of my house. It goes through one exterior wall with windows, possibly one interior wall, and that's pretty impressive, especially if the projected 10 year battery life holds true. Mounting it was easy enough, requiring cutting a proper sized hole in the top of the thick plastic tank.Now for the two design quirks.One is that you have to pair the receiver and transmitter EVERY TIME THE RECEIVER LOSES POWER. Trying to find the best place to put it inside your house? You better have a long extension cord, and then, having found the perfect spot, if you want to replace that long cord with something shorter, you will have to go to the tank, unscrew two Phillips screws, bring the transmitter to the house, re-pair the two, and take the transmitter back to the tank and re-mount it with the two screws. Power failures once or twice in the winter? Better put it on a UPS.I really don't understand why it has no battery for just a few minutes life. This is $130; raising the price to $150 if it included a 10 minute battery would be a no-brainer.The second quirk is that there are 8 dip switches to set to configure the tank size and shape. They've got a list of around a hundred settings (could go to 256 with 8 switches), ordered by height, with some notations for common tanks. I have just started at the first tank over 5 feet (mine is closer to 6 feet) and am trying each one in turn. It still is useful in a general sense, because all I really want to know is whether the float or other pump circuitry has died and is not pumping water. So far, it shows 50% when full, and 30% when near empty; I will keep trying combinations of switches until I find something better.It would be helpful if there were a better guide to choosing switches. Perhaps a formula would work -- empty and full heights, and diameter, that would be handy.But like I said at the beginning, there's nothing close to it that I can find for the price, so it gets 5 stars.