Stained Glass Association of America
The SGAA is a professional trade association, founded in 1903, whose membership consists of the finest architectural stained and decorative art glass artists and studios in the United States and around the world. The SGAA actively works for the betterment of the craft of stained glass and architectural art glass through various programs that are designed to benefit the members of the SGAA and the clients whom they serve.
I use these markers for children's illustrations, and they are wonderful. I do wish there were more color options for colors. I've found the light colors too few, especially when working with skin tones These pens last a very long time and work well with all sorts of papers. The tip options make this a great marker for precision coloring.