Convenient if you desire a black casting, adding color pigment is not necessary (can be polished and buffed to a high gloss shine) Unlike other black resins, ONYX does not contain mercury ONYX offers higher heat resistance vs. competitive black resins ONYX is less expensive vs. other black resins Shore 80D Smooth-Cast ONYX is a mercury-free urethane resin that cures quickly at room temperature to a deep black, solid plastic. ONYX offers the convenience of a 1A:1B by volume mix ratio and has a very low viscosity, so it is easy to mix and pour. POT LIFE: 5 mins; CURE TIME: 90 mins. , SHORE HARDNESS: 80D and offers higher physical properties and higher heat resistance vs. other general purpose resins. Consult the Technical Bulletin for more information. Read the MSDS sheet before using. Visit us at: www.smooth-on.com