627,201. Flexible tubes. CROPPER, H., RHODES, D., CROPPER, D. M., SMITH. H. F. MUMFORD-, and COMPOFLEX CO., Ltd. Sept. 2, 1947, Nos. 24169/47 and 23013/48. [Class 99(ii)] A flexible tube comprises an inner coil 1, one or more layers 2, 3 of textile material impregnated or coated with chloroprene polymer or the co-polymers of butadiene and acrylonitrile, which may be employed in the stabilized form, lap or spirally wound thereover, and an outer coil 4 applied under tension; the whole may be vulcanized. The layers may be impregnated or coated with Hycar OR.15 or OR.25 (Registered Trade Mark), and additional layers may be included which are impregnated or coated with Vulcaprene or Alkathene (Registered Trade Mark), or cellulose, rubber, or synthetic rubber or other plastics such as polyvinyl chloride may be used. Layers of kraft paper, cellulose, viscose, rubber or synthetic rubber or other plastics such as polyvinyl chloride may be included in the tube structure. An outer coating of heat-chemical and atmosphereresistant substance such as dow corning, or similar silicone varnish, Necol (Registered Trade Mark), or any similar silicon, plastic or resinous material may be applied, or a layer of textile material impregnated with any of these substances may be applied beneath the outer coil. One or both of the coils may be metal or a synthetic resin or other plastic.