Rubber hoses and tubing for air and vacuum systems for internal-combustion engines. Specification|Hardness, Pressure, Internal combustion engines, Vulcanized rubber, Diameter, Test specimens, Flexibility, Low temperatures, Heating tests, Dimensional tolerances, Adhesive strength, Compression set, Chemical-resistant materials, Vacuum engineering, Elongation at fracture, Suction hoses, Chemical-resistance tests, Mechanical properties of materials, Dimensional changes, Covers, Tensile strength, Temperature, Heat ageing tests, Pipes, Dimensions, Environment (working), Air, Extraction methods of analysis, Flexible pipes, Marking, Grades (quality), Ozone, Thermal testing