Black micro drip irrigation tubing is used as a feeder line from the 1/2" poly tubing (main line) to the plants. It's color gives you the ability to match the color of your project or surroundings. The primary difference between the vinyl and poly is that vinyl tubing tends to be more flexible than poly tubing.It may also be used as the basis for a complete system for containers and patio plants. Maximum working pressure for the micro tubing is 30 psiMaximum flow rate is 30 GPH. Micro tubing is .160 ID and .250 OD.1/4" clamps can be used to nail the tubing to a wooden structure, if need be.