I looked for quite a while to find reasonably priced paint pens. I found these paint pens on EBay to label my plastic pots. They are as good as the expensive ones. It took over a month to get them, but they work great and are good quality. The paint will not rub off the pots that I just tried. Only 99 cents each. I ordered 5 white ones, but dark colors are available for light colored pots. They are a fine/medium tip, (not a wide tip) but any wider would almost be a waste of paint. They are made of aluminum and have a little mixer/shaker ball inside. Good value. Go to ebay and enter this title that I copied and pasted just below. Hint: Might work to label a tree itself if it was needed.
Colorful Tyre Permanent Paint Pen Tire Metal Glass Lettering Marking Ink Marker
Colorful Tyre Permanent Paint Pen Tire Metal Glass Lettering Marking Ink Marker
Comment