This helps prevent any water from back siphoning into the drinking water. So water feeds in from this side, comes through here, check valve, and keeps water from coming back. So if on our sprinkler system we have a break on this side and we get dirt or anything in it, it won’t come back into the water and stays out of the drinking water? That’s correct. Okay so if you have an emergency, you can shut it off at one of these valves here. If it’s broken beyond this point over here on this backside, you have to shut it off at the water meter. There you have it. If you guys have any questions about back flows, give us a shout at 918-252-5296 or shoot us a message on the web at lbrtulsa.com.