TC-804 Jet Black A/B is a user friendly, low viscosity, 75D rigid urethane plastic that is Pre-Pigmented Black to save you time and money. This system features a convenient 1:1 by volume mixing ratio, 7-8 minutes working time, good heat resistance, and low moisture sensitivity producing tough, non-brittle castings. In many cases vacuum degassing is not required thanks to its low viscosity and low surface tension properties. Excellent at reproducing fine details without trapping air bubbles. Great for taxidermy, prototypes, model making, rotocasting, and parts of all kinds.