 Have you ever noticed that in some lawns, you've got little dry spots here and there and sometimes in the most oddest areas? Normally, that's because either you have a clogged head or maybe you don't have head-to-head coverage. That means that when you turn your sprinkler system on, one head should be able to spray all the way to the next head. Therefore, you get 100% saturation in that turf area.