Tubes, pipes and hoses and fittings therefor (for example, joints, elbows, flanges), of plastics:

Artificial guts (sausage casings) of hardened protein or of cellulosic plastics materials:

Fittings

Polymers of ethylene, in primary forms:

Polymers of propylene or of other olefins, in primary forms:

Polymers of styrene, in primary forms:

Polymers of vinyl chloride or of other halogenated olefins, in primary forms:

Polymers of vinyl acetate or of other vinyl esters, in primary forms; other vinyl polymers in primary forms:

Acrylic polymers in primary forms:

Polyacetals, other polyethers and epoxide resins, in primary forms; polycarbonates, alkyd resins, polyallyl esters and other polyesters, in primary forms: