We build them with durable glass-filled nylon and a fabric-reinforced diaphragm to ensure toughness and reliable, long-lasting performance. The diaphragm spring and bonnet studs and screws are made from corrosion-resistant stainless steel, and the flow-control stem is made of solid, heavy-duty brass. The self-flushing grit screen filters out sand and debris, and the slow-closing diaphragm reduces risk of water hammer.