Of polymers of propylene

39.17 - Tubes, pipes and hoses, and fittings therefor (for example, joints, elbows, flanges), of plastics. 3917.10 3917.21 3917.22 39 17.23 3917.29 - Artificial guts (sausage casings) of hardened protein or of cellulosic materials - Tubes, pipes and hoses, rigid : - - Of polymers of ethylene - - Of polymers of propylene - - Of polymers of vinyl chloride - - Of other plastics - Other tubes, pipes and hoses : 3917.31 - - Flexible tubes, pipes and hoses, having a minimum burst pressure of 27.6 3917.32 - - Other, not reinforced or otherwise combined with other materials, without 3917.33 - - Other, not reinforced or otherwise combined with other materials, with 3917.39 - - Other - Fittings 3917.40 MPa fittings fittings According to Note 8 to the Chapter, the expression " tubes, pipes and hoses " means : (i) hollow products, whether semi-manufactures or finished products, of a kind enerally used for conve n conducting or distributing gases or liqmds (for example, ribbe garden hose, perforate tu es), provided that they have an internal cross-section which is round, oval, rectangular (in whch the length does not exceed 1.5 times the width) or in the shape of a regular polygon; and 2t (ii) sausage casings (whether or not tied or otherwise further worked) and other lay-flat tubing. This heading also includes fittings of plastics for tubes, pipes and hoses (for example, joints, elbows, flanges). Tubes, pipes and hoses and fittings therefor ma be rigid or flexible and may be reinforced or otherwise combined with other materials. (For e classification of tubes, ipes, etc., of plastics combined with other materials, see the General Explanatory Note to this C apter.) R