Amazon.com: Temperature Activated Color Changing Thermochromic Paint (2 oz, RED changing to COLORLESS at 113F/45C) : Arts, Crafts & Sewing
Amazon.com : ATLANTA CHEMICAL ENGINEERING Temperature Heat Activated Color Changing Paint Thermochromic RED changing COLORLESS (translucent white) at 88 ⁰F : Arts, Crafts & Sewing