
3 inch or 2 inch FIA harness? The shoulder strap decision explained
A 3 inch and a 2 inch FIA harness are not two versions of the same belt. The shoulder width decides whether you can run it without a frontal head restraint, and the lap width is a separate choice again. Here is how to pick, with the OMP, Sparco, TRS, Schroth and Willans ranges laid out side by side.





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