These easy to use caps can make your do-it-yourself gardening projects much easier. Have you ever needed to cap off one end of a irrigation fitting in your hydroponic garden? You are left searching for some sort of leakproof plug. Here is your answer. The Hydro Flow® EZ Pull® End Caps are made from tough, flexible vinyl. They are easy to push on and pull off, yet provide a secure, leakproof fit.