Polytek's PT Flex 85 Liquid Rubber is a two-part, liquid polyurethane system that cures (RTV) to a yellow/amber, Shore A85 rubber. PT Flex Series rubbers were specifically designed for prototyping and model making applications and offer fast pour times (~5 minutes) and fast demold times (~2 hours).
 
Notes:
The color of polyurethane Part Bs may change in color from batch to batch or with time, but product performance is not affected.