Modular and easy to assemble. Print multiple pieces and put them together to make a column. Then feed your rubber tubing through the hollow rod to ensure that the water or nutrient solution flows smoothly through your system. The rod also ensures that the conduit or venturi is positioned vertically in the nutrient solution so that it can suck up the water efficiently. Visit our website (https://www.3dponics.com) and join our Google+ community (https://plus.google.com/u/0/communities/111638904033818784260)! Want to print this part? Search today's top 3D-printing services and materials to find the cheapest price for your project. Go to https://www.3Dprintler.com3D Printing Settings: -Low quality; 0.2 mm; 2 shells; 10% infill Tested on MakerBot, Ultimaker, M3D Micro and Formlabs