Wikipedia
Hexaethyl tetraphosphate
Hexaethyl tetraphosphate is a chemical compound with the chemical formula ( C H O) PO. It is a yellow, light amber-colored or brown liquid. The chemical is also known as HET. Its ChemSpider ID is 12420. It is a constituent of the insecticide Bladan. In the 1940s, it was about as significant an insecticide as DDT and was referred to as "another of DDT's rivals for fame" in a 1948 book.