ELASTOSIL® M4503 & T51 Silicone Rubber (Wacker RTV-2 Condensation Cure)ELASTOSIL® M4503 is a high-performance condensation cure RTV-2 silicone rubber, widely regarded as a standout product in the Wacker range. It offers excellent mechanical strength, durability, and resistance to casting resins, making it ideal for detailed mould making applications.This system is particularly well suited for reproducing models with pronounced undercuts, delivering reliable flexibility and tear resistance. Moulds produced with M4503 perform exceptionally well when casting materials such as polyester resin, wax, and plaster.Key FeaturesExcellent flow for accurate detail reproductionLow Shore A hardness (~25) for flexible mouldsHigh tear strength for durability and longevityOutstanding extensibility and elasticityLong-term stability of cured mechanical propertiesHigh resistance to casting resins, especially polyester systemsCan be thickened with Thixotropic C to create a brushable systemApplicationsELASTOSIL® M4503 is recommended for a wide range of mould making applications, including:General purpose mouldingLarge-scale mouldsResin casting (polyester, polyurethane)Plaster and wax castingModels with deep undercuts and complex geometryTechnical SpecificationsType: Condensation Cure RTV-2 Silicone ElastomerHardness: Shore A 25 ± 3Viscosity: Approx. 38,000 cpsPot Life (Work Time): ~30 minutesDemould Time: 10–20 hours (depending on conditions)Processing NotesM4503 is a pourable, two-component silicone system that cures at room temperature. For vertical surfaces or brush-on applications, it can be modified using Thixotropic C to achieve the desired consistency.