The classification of styrene-butadiene latex from France. Dear Mr. Price: In your letter dated September 15, 1998 you requested atariff classification ruling. The product, designated Rhodapas B187 D600, is described asstyrene-butadiene latex. The percentage by weight breakdown isgiven as styrene-1,3-butadiene copolymer (50 percent); poly-propylene glycol (less than 5 percent); and water (less than 50percent). The percent by weight of each monomer making up thepolymer is styrene (60 percent) and butadiene (40 percent). Thematerial is used as a gas migration blocking agent in thecementation of oil and gas wells.