Model-Pro Polyurethane Casting Resin 4 Making Models 2 Gallon Kit Make models, molds, protoypes, figurines, proof molds, make reproductions, etc.. Model-Pro turns from liquid to solid in 15 minutes and works excellent in rtv silcone molds. Model-Pro is a two component polyurethane casting resin which exhibits good impact resistane and strength. Same Day Shipping This is a 2 Gallon Kit contianing 16 pounds.