Designer Liner is clay based and heavily pigmented. Use this versatile product to create fine detail with lines, dots, and letters. The metal writer tip allows for ultimate control to draw ultra-fine or bold lines, typography and intricate illustrations. Designer Liner is best when used under non-moving transparent or semi-transparent glazes. Fires cone 06 - cone 6. Certified AP Non-toxic and Food Safe. Available in a variety of essential colors. Read more hints and tips at this link.