ISO 7840 Type A2 (25mm > 51mm). The tube is composed of a black nitrilerubber, with a smooth black chloroprenerubber cover. HOSE CONSTRUCTIONSmooth Rubber NBR Inner - Neoprene Rubber Outer. HOSE GRADEISO 7840 Type A1 (upto 19mm), ISO 7840 Type A2 (25mm and larger).
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