The Industry's #1 Plastic Residential Irrigation Valves. Rain Bird manufactures only the highest quality valves. Use DV/DVF series valves in locations where the use of a separate pressure vacuum breaker (PVB) or a double-check valve is required by city codes to protect against back flow. Check your local city codes to determine what type of valves are required. All of our valves work with any standard sprinkler timer.