Our patented Retro-Regulator turns any pop-up sprinkler body into a pressure-regulated system with a check valve in a matter of seconds. Now you can begin saving water and money without costly system modifications or replacing the entire sprinkler body at great expense. Choose between 30 or 40 PSI settings all in one part. This reduces not only cost but SKU count and inventory. Our regulator will fit inside most major manufacturers' sprinkler bodies in seconds.