I'm using this controller to charge and maintain a sealed lead-acid 18 ampere-hour battery at Little Fenway in Jerico, VT (http://www.littlefenway.com/ ). I was challenged to make the scoreboard lights (green and red balls, strikes, outs, hit, and error)come alive with no on-site power, and no buried wires. My radio-frequency-controlled solution includes a 12-watt solar panel and an 18-ah battery and receiver, driving the nine green and red LED lamp clusters on the scoreboard. The Morningstar Sunguard charge controller was inexpensive, has no relays or moving parts, and most importantly, adjusts its regulation voltage based on the temperature. In the foothills of Jericho, there are some seriously wild swings in temperature, so thermal compensation was a must for this system. The scoreboard is running well, the battery is sized for 40 hours of continuous operation over a cloudy 3-day weekend, and the Morningstar controller is doing its thing just right. Although I keep the charge controller inside the oversized battery box, along with the receiver and the SLA wetted glass-mat battery (so that the controller monitors the temperature inside the box where the battery is), it is just as weatherproof outside, due to its potted-up construction. I highly recommend this controller for small to medium indoors or outdoors installations.