Excellent unit, batteries last a long time. Use them on my rig for 3 weeks, the overflow batteries keep working. They've been on my truck for almost 3 months and they're still working great! I like the sun very much. I never have to keep it on after the first use. The only thing I want to say is that if you want to set up low and high alerts, you need to reset them all. No big deal once you have it where you want it