The WHATUP™ banner kit and markers are available at Walmart and online.
WHATUP™ Banner Kit
WHATUP™ Banner Markers
WHATUP™ banner markers hold up to the hardest rains but wipe off easily with a paper towel, leaving no residue. They can be used with the WHATUP™ banner kit or directly on glass surfaces and are available in a variety of colors.
Glass Chalk® Original Markers
The original Glass Chalk® markers allow you to turn building and car windows into banners or works of art that stand up to poor weather. When you want to change messages, they wipe clean with a towel. Original Glass Chalk® markers are non-toxic and come in several colors.