* Reliance 3bar Pressure Relief Valve With Female BSP 1/2 in BSP Female Connection and a BSP 1/2 Exhaust Port.
*1/2 inch Air Vacuum Relief Valve with BSP Male pipe thread delivers optimum performance and increased efficiency of a drip system by preventing back suctioning into the drip line. The relief valve allows air to escape the drip line during the system's initial start and until the pipe or drip line is full of water.