HED 3 Front to Rear Conversion?

I doubt this is possible, but I thought I remember someone talking about converting a hed3 from wheel to a rear wheel? Is this possible? Looking at the front hub I cannot envision it being possible but I thought I would ask to confirm.

Thanks,

RF

The front H3 wheel can be converted to a fixed gear rear wheel for track racing. There is a cap over a threaded surface that is used to screw a single cog and lock ring.

Thanks

RF
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