Hydro Flow?/Netafim?s Techline Combination Tee for 17 mm Drip Line Poly Tubing. Fits Techline CV Dripperline. These tee fittings connect to 3/4 inch Female Pipe Thread and have dual tee barbed tubing connectors that go inside the 17 mm poly tubing. Forms a tight, leak proof connection. Operating pressure is 0 to 30 psi.