Hub looks like this, the grooves in the cassette won’t fit over the higher part of the splines.
That look like an uniguide style freehub?
It look like one without the thread
It was a 10 speed only hub with higher splines to stop the cassette digging in, rare and weird and stupid.
@edscoble started
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Hub looks like this, the grooves in the cassette won’t fit over the higher part of the splines.