Tom came to my farm with my property manager (I lease) he said he didn't know how to impact the flow rate of the frost free hydrant. He also left when there was a leaky frost free hydrant in the barn, which he had seen. Furthermore, he talked about backflow preventers and concluded that I did NOT need one. However, just a few weeks later, he sent a letter to the property manager that I did. Way to sell out Tom. BTW I don't need a backflow preventer because the frost free hydrant acts as one on this system, but obviously Tom didn't know a thing about frost free hydrants.