Now that I got you to look, here's my problem. I have client that has 2 irrigated acres. Every week for the last 3 weeks "we" have broke a sprinkler while mowing. Problem is they are breaking at the nipples. Anyways these things arent visible and we are not clipping them. The weight of the mower must be breaking them. The system is over 10 years old and the nipples are rock hard. IMO the system needs to be updated, and although we are usually responsible for accidents these are not preventable and therefor not my fault. Any suggestions?