Capillary Rheometers, either single or twin bore, to meet the requirements of research and quality laboratories for thermoplastic polymers. PC controlled using dedicated VisualRHEO software in the CEASTView platform. Tests can be performed with constant shear rate and constant velocity. The data obtained from each of the barrels of the twin bore unit can be handled as independent tests. Particular advantage of the Twin Bore hardware configuration is the ability to obtain a number of measurements from a single test: a duplicate of the selected test, measurements for two dies with the same diameter but different lengths, and measurements for two different materials with identical test geometry.