Working in a sprinkler trench is tough enough-don't make it harder by using traditional pipe fitting methods that require hot, toxic glue, clamps or frustrating barbed fittings. Hydro-Rain offers a better way: Blu-Lock. Everything you do from the valve out, you can now do faster and easier with Blu-Lock. Primer? Glue? Clamps? Tools? With the Blue-Lock system, you don't need them! Simply stated, Blu-Lock by Hydro-Rain is the fastest, greenest, irrigation installation method in the world. Blu-Lock is for non-constant pressure, valve-out, cold water, outdoor direct burial irrigation connections only.