Translucent Tin Cure Silicone Rubber 20 Shore A RTV-2 Liquid Silicone for Resin Molds This translucent 20 Shore A tin cure (condensation-cure) RTV-2 liquid silicone rubber is a two-component mold-making silicone supplied as HN-620 in the HN-6XX series. Mixed at a simple 100:2 ratio by weight and cured at room temperature, it forms a clear, tough and tear-resistant elastomer with no oil bleed, fine pattern replication and multiple demolding cycles — a factory-direct solution