Select Mesh→Render→Fibers OR click the button on the toolbar. 
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Select a list of elements, and appropriate xi3 locations. You can include a several xi3 locations if you wish.
- Specify a length or click the “Auto” button to generate a good length based on the number of fiber vectors per element in the xi1 and xi2 directions.
- [Insert something about the “fiber elements per element in” options]