The belt i got is one that others who use the kickr have bought, and it's designed for a car - I know I'd like to think I can push big numbers, but even in my wildest dreams I don't think I can put out more power than a car I will look at it again when I can be bothered to find the time (or someone more technical than me wants to have a look) but for now I'll live with it as not impacting meI'm guessing just a tad, but I suspect that being a cheap belt it is prone to stretch under heavy load, whereas the original is better quality and has a higher tensile strength. Difficult to compare without data specs of. others belts