Netafim 32000-007860 TL050MFV-1 1/2" MPT Gal Automatic Flush Valve. Helps reduce maintenance to your irrigation system and increase dripline performance. For periodic flushing of your irrigation system at the start and end of each irrigation cycle. At the start and end of each cycle, a small amount of water passes through, flushing debris that may have accumulated in the system ensuring optimum system operation and performance.