Flame Retardant Bulk Curing Agent Ambersil Silicones Crosslinking / Coupling / Curing Agents Flame and Smoke Retardants Silicones (Si) SEALANT Flame Retardant Bulk Curing Agent For Use With RTV2018 To meet the increasing demand for greater safety, particularly in respect of flame retardancy, in domestic electrical equipment, Flame Retardant Bulk Curing Agent has been developed for use with Ambersil RTV2018 (Condensation Cure Silicone Rubber) Flame retardant bulk curing agent. Used in combination with condensation cure silicone rubbers. Provides flame retardancy.