This siloxane, also known as Methylbis(trimethylsilyloxy)silane, presents as a colorless to very pale-yellow liquid. Store in a cool, dark and well-ventilated place, under inert gas and protected from moisture. This substance is moisture sensitive and should be stored at ambient temperatures. 1,1,1,3,5,5,5-Heptamethyltrisiloxane is incompatible with oxidizing agents, acids, bases, water and metals. This highly flammable liquid and vapor causes skin irritation and serious eye irritation.