Poly Optic- Clear Casting ResinPoly Optic 1411 Clear Casting Resins are 1A: 1B by volume mix, clear, hard, D~80 polyurethane casting plastics that are great for making clear parts that look like water or glass where optical clarity is important. Vacuum and pressure casting are recommended for the best results to eliminate unwanted air bubbles. Can be color cast with Poly Color dyes. Heated molds are also recommended for improved results. Features Crystal clear High strength Rapid