The Self Piercing Emitters with a sharp barb makes it easy to install, no tools required. Optional insertion tool is available #747542. These emitters have a 1.74 psi internal check valve that helps prevent low emitter drainage holding back up to a 3.9 ft column of water. Prevents contaminants from being drawn into the emitter. The Self Piercing Emitters are pressure compensating and delivers the same flow from 10.15 to 58 psi. Exclusive TurboNet? flow path design regulates flow and provides continuous self-cleaning action during operation.