Neomarker Large Waterproof Marker Broad Tip - Blue
These waterproof neon markers are great as a sign marker, window marker or general glass marker. Writes on nearly anything...GLASS, PLASTIC, METAL, STONE, ACRYLIC, CERAMIC...etc. Stays on in the rain, but easily comes off with most window cleaners. A neon marker with a  inch wide tip for bold artwork gives you lots of control.