That would be 41 kilograms (force) per square millimeter. This converts to 58,325 (approx) lbs per square inch. I am presuming you are looking at this in the context of strength of materials. This tensile strength is usually stated in terms of some level of yield, deformation (strain) or fracture. But basically a one inch square of the material in question would support a load approaching 58,000 pounds....if I did my math correctly in the conversions.