ASTM B557, ASTM B348
Specific fixtures are available to guarantee the perfect clamping of round/flat specimens leaving space for the use of the extensometer with the gage length required by the Norm. Grips can be shouldered, threaded or prismatic for round specimens only, or wedge/hydraulic type for flat specimens. Clip On Extensometers with reduced gauge length as well as Micron, Video and Laser are available. For magnesium-laden alloys (non-plastic material with a clean break) a Micron Extensometer is recommended.