Tinius Olsen Tensile grips are used for uni-axial material testing where a sample is pulled apart from two ends. There are many variations of tensile grips for universal testing machines based on the force capacity of the procedure and the specific type of material and geometry. Many of these fixtures can use different types of inserts which can help to secure the sample. Selecting the right combination of grip and jaw inserts is critical to the success of any tensile testing application.