The tool that I am going to tell you about is for using herbicides such as RoundUp. The biggest mistakes that people make when using non-selective herbicides like RoundUp is overspray getting the herbicide on plants that they did not intend to spray, and over applying the product. If you spray to the point of run off, you are applying way too much.
The weed dabber is a tool used for spot treating weeds without getting the herbicide on other plants.
Start by going to your hardware store and buying a piece of 1- 1/2 PVC pipe. You only need a piece 30 long, but they might make you buy a 10′ section. It’s pretty cheap though. You’ll need a plastic PVC cap for one end of the pipe, and on the other end you’ll need an adapter to convert the PVC pipe to a standard pipe thread. You’ll have to let the clerk at the hardware store help you find the best combination of fittings to use. What you need to do is to get the PVC pipe reduced down to a male garden hose type fitting. Hardware stores sell brass fittings that convert standard pipe thread to the same thread used on garden hoses.
Probably what you’ll end up with is an adapter...