Product includes: comes with 20 pieces in a bag. Fits most 1/2" size tubing and 1/4" drip line (0.51 ID to 0.15 ID) Operating Pressure: Up to 45 PSI, Un 1/2" tube can be divided into four 1/4" tubes. For use with drip dispensing tube, drip bubble tube and emitter line. Anti-drop design: secure and easy installation. Press the barbed tee into the tube. Lock the tube with screw caps. High quality: high quality hard fitting, recycled material. Our barbed wire t-shirt is made of high quality material, we increased the wall thickness. It's durable. Application: Ideal for use with raised beds, residential, agricultural, greenhouse gardening and agricultural watering applications. How to install : 1. Loosen the nut. 2. Screw the nut into the 16mm PE pipe. 3. Use hot water to soften the 16mm PE pipe for about 30 seconds. 4. Insert the connector into the softened 16 PE pipe and tighten the nut. 5. Insert the middle part into the softened 4/7 mm pipe.