Rain Bird PRS05030S Drip Irrigation 30 PSI Retrofit Pressure Regulator for 1/2" Threaded Riser. Quickly and easily convert a standard 1/2" riser or a riser mounted shrub spray to a water-saving Drip irrigation zone. 1/2” female pipe threaded bottom inlet connects to any 1/2" male pipe threaded riser. Top outlet accepts a 1/2" threaded Drip manifold (sold separately) from which you can run 1/4" Drip tubing to operate emitters, bubblers, micro-sprays and 1/4” Drip emitter tubing. Constructed of highly durable UV and chemical-resistant materials to assure long life. Use with Rain Bird free flow manifold models (sold separately)