Without getting into the back story, modern washing machines, especially front loaders, have quite aggressive solenoid valves. I got this from a memo from Sioux Chief, eponymous manufacturer of hammer arresters. I had a small set on the LG washer here, and within a couple of years, those very aggressive valves had driven the pistons all the way to the top of the chamber and lost the air charge completely. I keep them on the shelf just to show them off. Sioux Chief recommends either a small arrester at both the washing machine and the valve, on both the hot & cold lines, or a much larger set. I went with the larger set and plumbed in one of the nice quarter turn single handle water valves.I had to buy a pair of water hammer arrestors- for some reason we didn't need them with the old Amana.