I have four solar Nite Guards on each side of the run at about 3' height. I put them up last fall before I even had any chickens. Got my chickens this March and have not seen any type of predator in my yard or around the coop and run at all. Don't know if it's because the Nite Guards work or because the predators haven't figured out that I have chickens yet. They're out there flashing away every night! I paid $99 for the set of four from McMurray. Sorry, I can't remember what I paid for shipping.