Mold Star 15 SLOW Moldmaking Silicone Rubber - Trial Unit TEAR RESISTANT - Mold Star silicones cure to soft, strong rubbers which are tear resistant and exhibit very low long term shrinkage *Packaging may vary* HEAT RESISTANT - Cured Mold Star rubber is heat resistant up to 450F (232C) and is suitable for casting low-temperature melt metal alloys CURING- Allow Mold Star 15 SLOW silicone rubber to cure for 4 hours at room temperature (73F/23C) before demolding. VACCUM DEGASSING - Although not necessary, vacuum degassing helps eliminate any entrapped air in pourable silicone rubber MOLD PREFORMACE - The physical life of the mold depends on how you use it (materials cast, frequency, etc.). Casting abrasive materials such as concrete can quickly erode mold detail, while casting non-abrasive materials (wax) will not affect mold detail. Before storing, the mold should be cleaned with a soap solution and wiped fully dry. Two part (or more) molds should be assembled. Molds should be stored on a level surface in a cool, dry environment