Classification of adhesive neoprene: treated as prepared glues under tariff, not mastics, assessments to be finalised accordingly Based on chemical composition, physical form, function and application, adhesive neoprene does not qualify as Mastics under Heading No. 32.14 and is classifiable as prepared glues and other prepared adhesives under Heading No. 35.06; the Central Board agrees with the Chief Chemist's opinion and directs that pending assessments be finalised accordingly and field formations and trade be informed.